Steps to reproduce:
Forward text message.  Type part of recipient address in To line.  Click Send button while autocomplete is still waiting.  Click again because the first click just told autocomplete to finish.  Evolution starts to send message and then crashes.  Couldn't use bug buddy to report this because bug buddy said that my request was malformed or something.  This is reproducible, so I did again and captured the stack trace from bug buddy before trying to submit it.

Stack trace:
Distribution: Fedora release 6.92 (Rawhide)
Gnome Release: 2.18.0 2007-03-23 (Red Hat, Inc)
BugBuddy Version: 2.18.0

System: Linux 2.6.20-1.2943.fc6 #1 SMP Wed Apr 4 16:06:04 EDT 2007 i686
X Vendor: The X.Org Foundation
X Vendor Release: 10299905
Selinux: No
Accessibility: Disabled
GTK+ Theme: Clearlooks
Icon Theme: Clearlooks

Memory status: size: 249720832 vsize: 249720832 resident: 38178816 share: 21221376 rss: 38178816 rss_rlim: 4294967295
CPU usage: start_time: 1176636520 rtime: 784 utime: 653 stime: 131 cutime:0 cstime: 2 timeout: 0 it_real_value: 0 frequency: 100

Backtrace was generated from '/usr/bin/evolution'

Using host libthread_db library "/lib/libthread_db.so.1".
[Thread debugging using libthread_db enabled]
[New Thread -1208662304 (LWP 32156)]
[New Thread -1421227120 (LWP 32746)]
[New Thread -1420493936 (LWP 32213)]
[New Thread -1317639280 (LWP 32193)]
[New Thread -1296266352 (LWP 32191)]
0x00cb5402 in __kernel_vsyscall ()

+ Trace 127927

----------- .xsession-errors (7 sec old) ---------------------
(evolution:32156): e-data-server-DEBUG: Loaded 22 categories
(evolution:32156): e-data-server-ui-DEBUG: ep_msg_send: in main thread? 1
(evolution:32156): gtkhtml-WARNING **: No such file or directory
(evolution:32156): gtkhtml-WARNING **: No such file or directory
(evolution:32156): e-data-server-ui-DEBUG: ep_msg_send: in main thread? 1
(evolution:32156): GLib-GObject-WARNING **: invalid uninstantiatable type `(null)' in cast to `GtkEntry'
(evolution:32156): Gtk-CRITICAL **: gtk_entry_get_text: assertion `GTK_IS_ENTRY (entry)' failed
(evolution:32156): GLib-GObject-WARNING **: invalid uninstantiatable type `(null)' in cast to `GtkEditable'
(evolution:32156): Gtk-CRITICAL **: gtk_editable_get_position: assertion `GTK_IS_EDITABLE (editable)' failed
--------------------------------------------------


Other information:
Bug buddy error:

Bug Buddy has encountered an error while submitting your report to the Bugzilla server.  Details of the error are included below.

Failed to parse the xml-rpc response.  Response follows:

Unable to parse XML-RPC Response

3

<?xml version="1.0" encoding="UTF-8"?>
<methodResponse><fault><value><struct><member><name>faultString</name><value><string>Application failed during request deserialization: 
not well-formed (invalid token) at line 23, column 0, byte 1575 at /usr/lib64/perl5/vendor_perl/5.8.8/x86_64-linux-thread-multi/XML/Parser.pm line 187
</string></value></member><member><name>faultCode</name><value><string>Client</string></value></member></struct></value></fault></methodResponse>