diff --git a/layout/reftests/svg/smil/motion/animateMotion-by-1.svg b/layout/reftests/svg/smil/motion/animateMotion-by-1.svg
index 755cf4c1e5c2..fdb31efef607 100644
--- a/layout/reftests/svg/smil/motion/animateMotion-by-1.svg
+++ b/layout/reftests/svg/smil/motion/animateMotion-by-1.svg
@@ -4,7 +4,7 @@
   <script xlink:href="../smil-util.js" type="text/javascript"/>
   <script type="text/javascript">
     function doTest() {
-      setTimeAndSnapshot(1, true);
+      setTimeAndSnapshot(101, true);
     }
     window.addEventListener("MozReftestInvalidate", doTest, false);
   </script>
@@ -17,25 +17,25 @@
   <!-- FIRST ROW -->
   <!-- Check that 'by' works at all -->
   <rect fill="lime" x="0" y="0" width="50" height="50">
-    <animateMotion by="100, 100" begin="0" dur="1" fill="freeze"/>
+    <animateMotion by="100, 100" begin="100" dur="1" fill="freeze"/>
   </rect>
 
   <!-- Check that 'by' is additive w/ 'by' -->
   <rect fill="lime" x="50" y="50" width="50" height="50">
-    <animateMotion by="60, 75" begin="0" dur="1" fill="freeze"/>
-    <animateMotion by="40, -25" begin="0" dur="1" fill="freeze"/>
+    <animateMotion by="60, 75" begin="100" dur="1" fill="freeze"/>
+    <animateMotion by="40, -25" begin="100" dur="1" fill="freeze"/>
   </rect>
 
   <!-- SECOND ROW -->
   <!-- Check that 'by' is additive w/ 'to' -->
   <rect fill="lime" width="50" height="50">
-    <animateMotion to="50,100" begin="0" dur="1" fill="freeze"/>
-    <animateMotion by="50, 50" begin="0" dur="1" fill="freeze"/>
+    <animateMotion to="50,100" begin="100" dur="1" fill="freeze"/>
+    <animateMotion by="50, 50" begin="100" dur="1" fill="freeze"/>
   </rect>
 
   <!-- Check that 'from-to' replaces 'by' -->
   <rect fill="lime" width="50" height="50">
-    <animateMotion by="500, 500" begin="0" dur="1" fill="freeze"/>
-    <animateMotion from="300,300" to="150,150" begin="0" dur="1" fill="freeze"/>
+    <animateMotion by="500, 500" begin="100" dur="1" fill="freeze"/>
+    <animateMotion from="300,300" to="150,150" begin="100" dur="1" fill="freeze"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/motion/animateMotion-from-to-1.svg b/layout/reftests/svg/smil/motion/animateMotion-from-to-1.svg
index e8aeed8ee264..065ee36b126c 100644
--- a/layout/reftests/svg/smil/motion/animateMotion-from-to-1.svg
+++ b/layout/reftests/svg/smil/motion/animateMotion-from-to-1.svg
@@ -4,7 +4,7 @@
   <script xlink:href="../smil-util.js" type="text/javascript"/>
   <script type="text/javascript">
     function doTest() {
-      setTimeAndSnapshot(1, true);
+      setTimeAndSnapshot(101, true);
     }
     window.addEventListener("MozReftestInvalidate", doTest, false);
   </script>
@@ -17,28 +17,28 @@
   <!-- FIRST ROW -->
   <!-- Check that 'from' gets applied at begin time -->
   <rect fill="lime" x="0" y="0" width="50" height="50">
-    <animateMotion from="100, 100" to="500, 500" begin="1" dur="1"/>
+    <animateMotion from="100, 100" to="500, 500" begin="101" dur="1"/>
   </rect>
 
   <!-- Check that 'to' gets hit at end time -->
   <rect fill="lime" x="0" y="0" width="50" height="50">
-    <animateMotion from="200,200" to="150,100" begin="0" dur="1" fill="freeze"/>
+    <animateMotion from="200,200" to="150,100" begin="100" dur="1" fill="freeze"/>
   </rect>
 
   <!-- SECOND ROW -->
   <!-- Check that animation effects are removed after end time
        (note that fill="remove" is default; just specifying it for clarity -->
   <rect fill="lime" x="100" y="150" width="50" height="50">
-    <animateMotion from="500,500" to="600,600" begin="0" dur="1" fill="remove"/>
+    <animateMotion from="500,500" to="600,600" begin="1000" dur="1" fill="remove"/>
   </rect>
   <rect fill="purple" x="-25" y="-25" width="25" height="25">
     <!-- With the purple rect's x/y offsets, this animateMotion path moves us
          around the 2nd row, 1st col -->
-    <animateMotion from="125,175" to="150,175" begin="0" dur="1" fill="remove"/>
+    <animateMotion from="125,175" to="150,175" begin="100" dur="1" fill="remove"/>
   </rect>
 
   <!-- Check interpolation halfway through animation -->
   <rect fill="lime" width="50" height="50">
-    <animateMotion from="200,100" to="100,200" begin="0.5" dur="1"/>
+    <animateMotion from="200,100" to="100,200" begin="100.5" dur="1"/>
   </rect>
 </svg>
diff --git a/layout/reftests/svg/smil/motion/animateMotion-rotate-1a.svg b/layout/reftests/svg/smil/motion/animateMotion-rotate-1a.svg
index 368ffbc50f92..414a6c718be4 100644
--- a/layout/reftests/svg/smil/motion/animateMotion-rotate-1a.svg
+++ b/layout/reftests/svg/smil/motion/animateMotion-rotate-1a.svg
@@ -11,7 +11,7 @@
   <script xlink:href="../smil-util.js" type="text/javascript"/>
   <script type="text/javascript">
     function doTest() {
-      setTimeAndSnapshot(1, true);
+      setTimeAndSnapshot(101, true);
     }
     window.addEventListener("MozReftestInvalidate", doTest, false);
   </script>
@@ -25,7 +25,7 @@
   <!-- Check that 'rotate' gets applied at begin time -->
   <g>
     <animateMotion from="150, 100" to="500, 500" rotate="90"
-                   begin="1" dur="1"/>
+                   begin="101" dur="1"/>
     <rect class="test" x="0" y="0" width="20" height="50"/>
     <rect class="test" x="0" y="0" width="50" height="20"/>
   </g>
@@ -33,7 +33,7 @@
 
   <!-- Check that 'rotate' gets applied at end time -->
   <g>
-    <animateMotion from="600, 700" to="200, 150" rotate="180" begin="0"
+    <animateMotion from="600, 700" to="200, 150" rotate="180" begin="100"
                    dur="1" fill="freeze"/>
     <rect class="test" x="0" y="0" width="20" height="50"/>
     <rect class="test" x="0" y="0" width="50" height="20"/>
@@ -44,7 +44,7 @@
   <!-- Check that rotate combines with existing rotate -->
   <g transform="rotate(90)">
     <animateMotion from="150,200" to="600,600" rotate="90"
-                   begin="1" dur="1"/>
+                   begin="101" dur="1"/>
     <rect class="test" x="0" y="0" width="20" height="50"/>
     <rect class="test" x="0" y="0" width="50" height="20"/>
   </g>
@@ -53,9 +53,9 @@
   <!-- Check additivity of <animateMotion> "rotate" adds -->
   <g>
     <animateMotion from="100,100" to="100,200" rotate="90"
-                   begin="0.5" dur="1"/>
+                   begin="100.5" dur="1"/>
     <animateMotion by="100,-200" rotate="90"
-                   begin="0.5" dur="1"/>
+                   begin="100.5" dur="1"/>
     <rect class="test" x="0" y="0" width="20" height="50"/>
     <rect class="test" x="0" y="0" width="50" height="20"/>
   </g>
diff --git a/layout/reftests/svg/smil/motion/animateMotion-rotate-1b.svg b/layout/reftests/svg/smil/motion/animateMotion-rotate-1b.svg
index 84e740491d36..8c4287d33ed3 100644
--- a/layout/reftests/svg/smil/motion/animateMotion-rotate-1b.svg
+++ b/layout/reftests/svg/smil/motion/animateMotion-rotate-1b.svg
@@ -11,7 +11,7 @@
   <script xlink:href="../smil-util.js" type="text/javascript"/>
   <script type="text/javascript">
     function doTest() {
-      setTimeAndSnapshot(1, true);
+      setTimeAndSnapshot(101, true);
     }
     window.addEventListener("MozReftestInvalidate", doTest, false);
   </script>
@@ -25,7 +25,7 @@
   <!-- Check that 'rotate' gets applied at begin time -->
   <g>
     <animateMotion from="150, 100" to="500, 500" rotate="100grad"
-                   begin="1" dur="1"/>
+                   begin="101" dur="1"/>
     <rect class="test" x="0" y="0" width="20" height="50"/>
     <rect class="test" x="0" y="0" width="50" height="20"/>
   </g>
@@ -33,7 +33,7 @@
 
   <!-- Check that 'rotate' gets applied at end time -->
   <g>
-    <animateMotion from="600, 700" to="200, 150" rotate="200grad" begin="0"
+    <animateMotion from="600, 700" to="200, 150" rotate="200grad" begin="100"
                    dur="1" fill="freeze"/>
     <rect class="test" x="0" y="0" width="20" height="50"/>
     <rect class="test" x="0" y="0" width="50" height="20"/>
@@ -44,7 +44,7 @@
   <!-- Check that rotate combines with existing rotate -->
   <g transform="rotate(90)">
     <animateMotion from="150,200" to="600,600" rotate="100grad"
-                   begin="1" dur="1"/>
+                   begin="101" dur="1"/>
     <rect class="test" x="0" y="0" width="20" height="50"/>
     <rect class="test" x="0" y="0" width="50" height="20"/>
   </g>
@@ -53,9 +53,9 @@
   <!-- Check additivity of <animateMotion> "rotate" adds -->
   <g>
     <animateMotion from="100,100" to="100,200" rotate="100grad"
-                   begin="0.5" dur="1"/>
+                   begin="100.5" dur="1"/>
     <animateMotion by="100,-200" rotate="100grad"
-                   begin="0.5" dur="1"/>
+                   begin="100.5" dur="1"/>
     <rect class="test" x="0" y="0" width="20" height="50"/>
     <rect class="test" x="0" y="0" width="50" height="20"/>
   </g>
diff --git a/layout/reftests/svg/smil/motion/animateMotion-rotate-2.svg b/layout/reftests/svg/smil/motion/animateMotion-rotate-2.svg
index 930493e2678a..7f6fcc7cf590 100644
--- a/layout/reftests/svg/smil/motion/animateMotion-rotate-2.svg
+++ b/layout/reftests/svg/smil/motion/animateMotion-rotate-2.svg
@@ -25,7 +25,7 @@
   <script xlink:href="../smil-util.js" type="text/javascript"/>
   <script type="text/javascript">
     function doTest() {
-      setTimeAndSnapshot(1, true);
+      setTimeAndSnapshot(101, true);
     }
     window.addEventListener("MozReftestInvalidate", doTest, false);
   </script>
@@ -40,13 +40,13 @@
     <!-- And here's a stack of elements animated with 'animateMotion' that
          should end up there. -->
     <use xlink:href="#marker" class="testBegin">
-      <animateMotion from="20,20" to="40,40" rotate="auto" begin="1s" dur="1s"/>
+      <animateMotion from="20,20" to="40,40" rotate="auto" begin="101s" dur="1s"/>
     </use>
     <use xlink:href="#marker" class="testEnd">
-      <animateMotion by="20,20" rotate="auto" dur="1s" fill="freeze"/>
+      <animateMotion by="20,20" rotate="auto" begin="100" dur="1s" fill="freeze"/>
     </use>
     <use xlink:href="#marker" class="mask">
-      <animateMotion by="40,40" rotate="auto" dur="2s"/>
+      <animateMotion by="40,40" rotate="auto" begin="100s" dur="2s"/>
     </use>
   </g>
 </svg>
diff --git a/layout/reftests/svg/smil/motion/animateMotion-to-overridden-1.svg b/layout/reftests/svg/smil/motion/animateMotion-to-overridden-1.svg
index cca246567c35..2c6179640ae7 100644
--- a/layout/reftests/svg/smil/motion/animateMotion-to-overridden-1.svg
+++ b/layout/reftests/svg/smil/motion/animateMotion-to-overridden-1.svg
@@ -4,7 +4,7 @@
   <script xlink:href="../smil-util.js" type="text/javascript"/>
   <script type="text/javascript">
     function doTest() {
-      setTimeAndSnapshot(1, true);
+      setTimeAndSnapshot(101, true);
     }
     window.addEventListener("MozReftestInvalidate", doTest, false);
   </script>
@@ -21,30 +21,30 @@
   <!-- Single-point path specified with "values" attribute: -->
   <g transform="translate(0,0)">
     <rect width="20" height="20" fill="red">
-      <animateMotion values="20,0" dur="2"/>
+      <animateMotion values="20,0" dur="2" begin="100"/>
     </rect>
     <rect width="20" height="20" fill="lime">
-      <animateMotion values="20,0" dur="2" to="-50,0"/>
+      <animateMotion values="20,0" dur="2" to="-50,0" begin="100"/>
     </rect>
   </g>
 
   <!-- Multi-point path specified with "values" attribute: -->
   <g transform="translate(0,30)">
     <rect width="20" height="20" fill="red">
-      <animateMotion values="20,0; 80,0" dur="2"/>
+      <animateMotion values="20,0; 80,0" dur="2" begin="100"/>
     </rect>
     <rect width="20" height="20" fill="lime">
-      <animateMotion values="20,0; 80,0" dur="2" to="-50,0"/>
+      <animateMotion values="20,0; 80,0" dur="2" to="-50,0" begin="100"/>
     </rect>
   </g>
 
   <!-- Path specified with "path" attribute: -->
   <g transform="translate(0,60)">
     <rect width="20" height="20" fill="red">
-      <animateMotion path="m0,0 h100" dur="2"/>
+      <animateMotion path="m0,0 h100" dur="2" begin="100"/>
     </rect>
     <rect width="20" height="20" fill="lime">
-      <animateMotion path="m0,0 h100" dur="2" to="-50,0"/>
+      <animateMotion path="m0,0 h100" dur="2" to="-50,0" begin="100"/>
     </rect>
   </g>
 
@@ -52,10 +52,10 @@
   <path id="p" d="m0,0 h100"/>
   <g transform="translate(0,90)">
     <rect width="20" height="20" fill="red">
-      <animateMotion dur="2"><mpath xlink:href="#p"/></animateMotion>
+      <animateMotion dur="2" begin="100"><mpath xlink:href="#p"/></animateMotion>
     </rect>
     <rect width="20" height="20" fill="lime">
-      <animateMotion dur="2" to="-50,0"><mpath xlink:href="#p"/></animateMotion>
+      <animateMotion dur="2" to="-50,0" begin="100"><mpath xlink:href="#p"/></animateMotion>
     </rect>
   </g>
 </svg>
diff --git a/layout/reftests/svg/smil/sort/sort-additive-1.svg b/layout/reftests/svg/smil/sort/sort-additive-1.svg
index 53f452f00418..e60ff0a15f4b 100644
--- a/layout/reftests/svg/smil/sort/sort-additive-1.svg
+++ b/layout/reftests/svg/smil/sort/sort-additive-1.svg
@@ -10,7 +10,7 @@
       var low = document.getElementById("low");
       low.parentNode.insertBefore(low, low.parentNode.firstChild);
 
-      setTimeAndSnapshot(3.1, true);
+      setTimeAndSnapshot(103.1, true);
     }
     window.addEventListener("MozReftestInvalidate", swapAnimations, false);
   ]]></script>
@@ -29,8 +29,8 @@
   <g transform="translate(5, 5)">
     <rect style="stroke: black; fill: lightskyblue" x="0" y="0" width="30"
     height="30">
-     <animate attributeName="x" from="0" to="100" dur="3s" fill="freeze"/>
-     <animate attributeName="x" from="0" to="100" dur="3s" fill="freeze"/>
+     <animate attributeName="x" from="0" to="100" begin="100s" dur="3s" fill="freeze"/>
+     <animate attributeName="x" from="0" to="100" begin="100s" dur="3s" fill="freeze"/>
     </rect>
   </g>
   <!-- Additive group -->
@@ -39,8 +39,8 @@
   <g transform="translate(5, 45)">
     <rect style="stroke: black; fill: lightskyblue" x="0" y="0" width="30"
     height="30">
-      <animate attributeName="x" from="0" to="100" dur="3s" fill="freeze"/>
-      <animate attributeName="x" from="0" to="100" dur="3s" fill="freeze"
+      <animate attributeName="x" from="0" to="100" begin="100s" dur="3s" fill="freeze"/>
+      <animate attributeName="x" from="0" to="100" begin="100s" dur="3s" fill="freeze"
         additive="sum"/>
     </rect>
   </g>
@@ -51,9 +51,9 @@
   <g transform="translate(5, 85)">
     <rect style="stroke: black; fill: lightskyblue" x="0" y="0" width="30"
       height="30">
-      <animate attributeName="x" from="0" to="100" dur="3s" fill="freeze"
+      <animate attributeName="x" from="0" to="100" begin="100s" dur="3s" fill="freeze"
         additive="sum"/>
-     <animate attributeName="x" from="0" to="100" dur="3s" fill="freeze"/>
+     <animate attributeName="x" from="0" to="100" begin="100s" dur="3s" fill="freeze"/>
     </rect>
   </g>
   <!-- Additive group -->
@@ -63,9 +63,9 @@
   <g transform="translate(5, 125)">
     <rect style="stroke: black; fill: lightskyblue" x="0" y="0" width="30"
       height="30">
-      <animate attributeName="x" from="0" to="100" dur="3s" fill="freeze"
-        additive="sum" begin="1ms"/>
-      <animate attributeName="x" from="0" to="100" dur="3s" fill="freeze"/>
+      <animate attributeName="x" from="0" to="100" begin="100.001s" dur="3s" fill="freeze"
+        additive="sum"/>
+      <animate attributeName="x" from="0" to="100" begin="100s" dur="3s" fill="freeze"/>
     </rect>
   </g>
   <!-- Not additive group -->
@@ -74,9 +74,8 @@
   <g transform="translate(5, 165)">
     <rect style="stroke: black; fill: lightskyblue" x="0" y="0" width="30"
       height="30">
-      <animate attributeName="x" from="0" to="100" dur="3s" fill="freeze"
-        begin="1ms"/>
-      <animate attributeName="x" from="0" to="100" dur="3s" fill="freeze"
+      <animate attributeName="x" from="0" to="100" begin="100.001s" dur="3s" fill="freeze"/>
+      <animate attributeName="x" from="0" to="100" begin="100s" dur="3s" fill="freeze"
         additive="sum"/>
     </rect>
   </g>
@@ -85,8 +84,8 @@
   <g transform="translate(5, 205)">
     <rect style="stroke: black; fill: lightskyblue" x="0" y="0" width="30"
       height="30">
-      <animate attributeName="x" from="0" to="100" dur="3s" fill="freeze"/>
-      <animate attributeName="x" by="100" dur="3s" fill="freeze"
+      <animate attributeName="x" from="0" to="100" begin="100s" dur="3s" fill="freeze"/>
+      <animate attributeName="x" by="100" dur="3s" begin="100s" fill="freeze"
         additive="replace"/>
     </rect>
   </g>
@@ -97,8 +96,8 @@
   <g transform="translate(5, 245)">
     <rect style="stroke: black; fill: lightskyblue" x="0" y="0" width="30"
       height="30">
-      <animate attributeName="x" from="0" to="100" dur="3s" fill="freeze"/>
-      <animate attributeName="x" from="0" to="100" dur="3s" fill="freeze"
+      <animate attributeName="x" from="0" to="100" begin="100s" dur="3s" fill="freeze"/>
+      <animate attributeName="x" from="0" to="100" begin="100s" dur="3s" fill="freeze"
         additive="sum" id="low"/>
     </rect>
   </g>
@@ -109,9 +108,9 @@
   <g transform="translate(5, 285)">
     <rect style="stroke: black; fill: lightskyblue" x="0" y="0" width="30"
       height="30">
-      <animate attributeName="x" from="0" to="100" dur="3s" fill="freeze"
+      <animate attributeName="x" from="0" to="100" begin="100s" dur="3s" fill="freeze"
         additive="sum" id="high"/>
-      <animate attributeName="x" from="0" to="100" dur="3s" fill="freeze"/>
+      <animate attributeName="x" from="0" to="100" begin="100s" dur="3s" fill="freeze"/>
     </rect>
   </g>
 </svg>