Mail 2.1 Crashing! Reinstall? Help!

Question

Mail has begun crashing while collecting email.
The tale:
It's an ole G4 Quicksilver and the drives are getting pretty full. I get a lot of email through various POP accounts and recently i've had trouble getting Mail to collect it.
I leave the Activity Window open so i know how it's progressing. Lately, it begins collecting mail fine, then it bogs down and though sucking a tremendous amount of computing power, it accomplishes nothing.
After several minutes in this state, it crashes.
I took several routes to try to correct the problem, retrying Mail after one or more changes, and none were effective.
Attempted solutions:
• Retarted Mail
• Rebooted the system
• Junked Prefs
• Executed System Maintenance Routines
• Cleared caches
• Rebuilt Mailboxes*
As i was rebuilding a large mailbox the system became similarly slow and it was taking a very long time.
Examining console logs, system logs, and crash logs and by observing processes, i had determined it was a virtual memory problem. I had little space on the drive and it was likely very fragmented. During the rebuild that space nearly disappeared completely.
I freed up around 30 GB (up from 12).
Mail crashed when collecting email, just the same. It doesn't crash every time if i collect email from one account at a time and there aren't a huge number of emails to be retrieved.
In the Mail crash log the last time i tried, the crashed thread looked very peculiar:
<pre>Thread 17 Crashed:
0 libSystem.B.dylib 0x900101bc __vfprintf + 40
1 libSystem.B.dylib 0x90029f8c vsnprintf + 300
2 libxml2.2.dylib 0x92c929d4 __xmlRaiseError + 448
3 libxml2.2.dylib 0x92cc311c xlinkIsLink + 848
4 libxml2.2.dylib 0x92cc7ff4 htmlParseElement + 260
5 libxml2.2.dylib 0x92cc7e10 htmlParseCharRef + 5248
6 libxml2.2.dylib 0x92cc8100 htmlParseElement + 528
7 libxml2.2.dylib 0x92cc7e10 htmlParseCharRef + 5248
8 libxml2.2.dylib 0x92cc8100 htmlParseElement + 528
9 libxml2.2.dylib 0x92cc7e10 htmlParseCharRef + 5248
10 libxml2.2.dylib 0x92cc8100 htmlParseElement + 528
11 libxml2.2.dylib 0x92cc7e10 htmlParseCharRef + 5248
12 libxml2.2.dylib 0x92cc8100 htmlParseElement + 528
13 libxml2.2.dylib 0x92cc7e10 htmlParseCharRef + 5248
14 libxml2.2.dylib 0x92cc8100 htmlParseElement + 528
15 libxml2.2.dylib 0x92cc7e10 htmlParseCharRef + 5248
16 libxml2.2.dylib 0x92cc8100 htmlParseElement + 528
</pre>It continued on with the same two lines repeating to line 508!
Unable to figure out what more to do, i decided to try to reinstall the Mail app. I cannot find a way to do this!
I moved Mail 2.1 out of the Applications folder and reinstalled 2.0 from my Tiger disc. "Software Update" will not return Mail to version 2.1, or whatever is newest.
I don't see where it's possible to obtain just Mail 2.1 on the Apple site.
What should i do now?
PowerMac G4 733 MHz Quicksilver - 1.5GB   Mac OS X (10.4.7)   Lacie/Pioneer 106d DVD±RW - G5 30GB iPod

Answer 1

Verify/repair the startup disk (not just permissions), as described here:
The Repair functions of Disk Utility: what's it all about?
After having fixed all filesystem issues, if any, move Mail from /Applications/ to the Trash, and reinstall it as described here:
Custom installs in Mac OS X 10.4
If the version of the system software on your installation disks is earlier than what you’re using now (and only in that case), then you must also reinstall the Combo Update for the type of computer and the version of Mac OS X you’re using, to bring Mail back in sync with the rest of the system:
About the Mac OS X 10.4.8 Combo Update
Mac OS X 10.4.8 Combo Update for PPC
Mac OS X 10.4.8 Combo Update for Intel
You may also want to read the following articles for guidelines on how to properly install system updates:
Troubleshooting installation and software updates
Installing software updates
Basically, you should verify/repair the startup disk before installing the update, no applications should be running while installing it, and you may experience unexpected results if you have third-party system software modifications (not normal applications) installed.
The above won’t solve the problem, but will allow us to at least troubleshoot it properly. Post back with your observations when done.