diff --git a/caps/src/Makefile.in b/caps/src/Makefile.in
index 7d28bc10753a..f7dcba0a95ab 100644
--- a/caps/src/Makefile.in
+++ b/caps/src/Makefile.in
@@ -46,7 +46,7 @@ CPPSRCS		=	        \
 		nsCCodeSourcePrincipal.cpp	\
 		$(NULL)
 
-REQUIRES	= xpcom security layer js jar zlib pref img util rdf caps 
+REQUIRES	= xpcom security layer js jar pref img util rdf caps 
 
 ifndef MOZ_NATIVE_ZLIB
 REQUIRES += zlib
diff --git a/modules/libimg/src/Makefile.in b/modules/libimg/src/Makefile.in
index a2d60d178747..e6839e09d94f 100644
--- a/modules/libimg/src/Makefile.in
+++ b/modules/libimg/src/Makefile.in
@@ -83,7 +83,7 @@ CPPSRCS		= color.cpp \
 
 EXPORTS		= PIMGCB.h PPSIMGCB.h
 
-REQUIRES	= jtools java nspr dbm util img layer js xpcom
+REQUIRES	= jtools java dbm util img layer js xpcom
 
 ifdef NU_CACHE
 REQUIRES 	+= cache
diff --git a/modules/softupdt/src/Makefile.in b/modules/softupdt/src/Makefile.in
index 0b96aa82ce7e..bfdf1dd8ed68 100644
--- a/modules/softupdt/src/Makefile.in
+++ b/modules/softupdt/src/Makefile.in
@@ -30,7 +30,11 @@ MODULE		= softupdate
 LIBRARY_NAME	= softupdate
 
 REQUIRES	= softupdt js java net dbm img util layer pref \
-		  jar security lay style libreg network progress base xpcom caps zlib plugin oji ojiimpl
+		  jar security lay style libreg network progress base xpcom caps plugin oji ojiimpl
+
+ifndef MOZ_NATIVE_ZLIB
+REQUIRES	+= zlib
+endif
 
 INCLUDES	+= -I$(topsrcdir)/base/src
 
diff --git a/modules/softupdt/src/nsdiff/Makefile.in b/modules/softupdt/src/nsdiff/Makefile.in
index 98f360cd56ed..c31c6f36df65 100644
--- a/modules/softupdt/src/nsdiff/Makefile.in
+++ b/modules/softupdt/src/nsdiff/Makefile.in
@@ -22,7 +22,11 @@ srcdir		= @srcdir@
 
 include $(DEPTH)/config/autoconf.mk
 
-REQUIRES	= softupdt zlib
+REQUIRES	= softupdt
+
+ifndef MOZ_NATIVE_ZLIB
+REQUIRES	+= zlib
+endif
 
 CSRCS		= nsdiff.c crc32.c
 
diff --git a/network/cnvts/Makefile.in b/network/cnvts/Makefile.in
index ba578d549da7..78e8cc753ba1 100644
--- a/network/cnvts/Makefile.in
+++ b/network/cnvts/Makefile.in
@@ -68,6 +68,10 @@ endif
 EXPORTS := $(addprefix $(srcdir)/, $(EXPORTS))
 
 REQUIRES	= network img lay layer util parse pref js \
-	security marimurl style zlib softupdt mimetype ldap
+	security marimurl style softupdt mimetype ldap
+
+ifndef MOZ_NATIVE_ZLIB
+REQUIRES	+= zlib
+endif
 
 include $(topsrcdir)/config/rules.mk