Add two more FAQs: `why don't you use VirtualLock()' and `are you

based on OpenSSH'.

[originally from svn r1825]

doc/faq.but

@@ -1,4 +1,4 @@
-\versionid $Id: faq.but,v 1.30 2002/07/09 11:34:10 jacob Exp $
+\versionid $Id: faq.but,v 1.31 2002/08/09 09:11:09 simon Exp $
 
 \A{faq} PuTTY FAQ
 
@@ -795,6 +795,16 @@ all. For this reason we now believe PuTTY's DSA implementation is
 probably OK. However, if you have the choice, we still recommend you
 use RSA instead.
 
+\S{faq-virtuallock}{Question} Couldn't Pageant use \c{VirtualLock()}
+to stop private keys being written to disk?
+
+Unfortunately not. The \c{VirtualLock()} function in the Windows API
+doesn't do a proper job: it may prevent small pieces of a process's
+memory from being paged to disk while the process is running, but it
+doesn't stop the process's memory as a whole from being swapped
+completely out to disk when the process is long-term inactive. And
+Pageant spends most of its time inactive.
+
 \H{faq-admin} Administrative questions
 
 \S{faq-domain}{Question} Would you like me to register you a nicer
@@ -892,6 +902,15 @@ developers. If you want to be sure your donation is going towards
 something worthwhile, ask us first. If you don't like these terms,
 feel perfectly free not to donate. We don't mind.
 
+\H{faq-misc} Miscellaneous questions
+
+\S{faq-openssh}{Question} Is PuTTY a port of OpenSSH, or based on
+OpenSSH?
+
+No, it isn't. PuTTY is almost completely composed of code written
+from scratch for PuTTY. The only code we share with OpenSSH is the
+detector for SSH1 CRC compensation attacks, written by CORE SDI S.A.
+
 \S{faq-sillyputty}{Question} Where can I buy silly putty?
 
 You're looking at the wrong web site; the only PuTTY we know about