Created attachment 149142 [details]
created with strace -f evolution > evol.strace 2>&1

Thanks for taking the time to report this bug.
Unfortunately, that stack trace is missing some elements that will help a lot to solve the problem, so it will be hard for the developers to fix that crash. Can you get us a stack trace with debugging symbols? Please see http://live.gnome.org/GettingTraces for more information on how to do so and reopen this bug or report a new one. Thanks in advance!

hope this is more helpful. strace seems not affected by debug symbols. 

after uninstalling evolution-exchange, imap accounts work as usual.

valsasna@aubergine:~$ dpkg -l|grep dbg
...
ii  evolution-data-server-dbg                  2.28.1-0ubuntu1                                      evolution database backend server with debug
ii  evolution-dbg                              2.28.1-0ubuntu2                                      debugging symbols for Evolution
ii  evolution-exchange-dbg                     2.28.1-0ubuntu1                                      Exchange plugin for Evolution with debugging
...

valsasna@aubergine:~$ gdb evolution
GNU gdb (GDB) 7.0-ubuntu
Copyright (C) 2009 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "i486-linux-gnu".
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>...
Reading symbols from /usr/bin/evolution...Reading symbols from /usr/lib/debug/usr/bin/evolution...done.
(no debugging symbols found)...done.
(gdb) run
Starting program: /usr/bin/evolution 
[Thread debugging using libthread_db enabled]
e-data-server-ui-Message: Unable to find password(s) in keyring (Keyring reports: Nessun risultato corrispondente)
e-data-server-ui-Message: Il file chiavi non presenta il gruppo "Passwords-Exchange"
** (evolution:6944): DEBUG: mailto URL command: evolution %s
** (evolution:6944): DEBUG: mailto URL program: evolution
[New Thread 0xb66ccb70 (LWP 6958)]
[Thread 0xb66ccb70 (LWP 6958) exited]
[New Thread 0xb66ccb70 (LWP 6959)]
[New Thread 0xb5ecbb70 (LWP 6960)]
[New Thread 0xb56c5b70 (LWP 6961)]
[New Thread 0xb4ec4b70 (LWP 6962)]
[New Thread 0xb46bdb70 (LWP 6963)]
[New Thread 0xb3cffb70 (LWP 6964)]
[New Thread 0xb34feb70 (LWP 6965)]
[New Thread 0xb2cfdb70 (LWP 6966)]
[New Thread 0xb24fcb70 (LWP 6967)]
[New Thread 0xb1cfbb70 (LWP 6968)]
[New Thread 0xb14fab70 (LWP 6969)]
[New Thread 0xb0cf9b70 (LWP 6970)]
[New Thread 0xb04f8b70 (LWP 6971)]
[New Thread 0xafcf7b70 (LWP 6972)]
[New Thread 0xaf4f6b70 (LWP 6973)]

** (evolution:6944): CRITICAL **: atk_object_set_name: assertion `name != NULL' failed
[Thread 0xaf4f6b70 (LWP 6973) exited]
[New Thread 0xaf4f6b70 (LWP 6974)]
[New Thread 0xaecf5b70 (LWP 6975)]
[New Thread 0xae4f4b70 (LWP 6976)]
[New Thread 0xadcf3b70 (LWP 6977)]
[Thread 0xadcf3b70 (LWP 6977) exited]
[New Thread 0xadcf3b70 (LWP 6978)]

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0xb1cfbb70 (LWP 6968)]
0x02f0ca7b in exchange_get_folder_info (store=0x81e5660, top=0x0, flags=7, ex=0x8534c34) at camel-exchange-store.c:735
735	camel-exchange-store.c: Nessun file o directory.
	in camel-exchange-store.c
(gdb)

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0xb1cfbb70 (LWP 6968)]
0x02f0ca7b in exchange_get_folder_info (store=0x81e5660, top=0x0, flags=7,
ex=0x8534c34) at camel-exchange-store.c:735
735    camel-exchange-store.c: Nessun file o directory.
    in camel-exchange-store.c
(gdb)  <- "Here wrote bt full"

example:
(gdb) bt full

and paste the stacktrace, thank :-)

sorry:

...
Program received signal SIGSEGV, Segmentation fault.

+ Trace 219465

(gdb)

Thanks for the bug report. This particular bug has already been reported into
our bug tracking system, but please feel free to report any further bugs you
find.

*** This bug has been marked as a duplicate of bug 528022 ***

Hi,

looking at the stack traces, I'm not sure it is correct to consider Bug 603836 a duplicate of bug 528022: the two stack traces have the same "lower part", but different "upper parts"
  
my trace ends at

#0 exchange_get_folder_info
at camel-exchange-store.c line 735

while the one from 528022 is at a different point in camel-exchange-store.c (using the same version of evolution, but distribution patches //may// account for that), and enters several more functions, which suggests the error may occur in a different code path.

#  #0  __kernel_vsyscall
# #1 __lll_mutex_lock_wait
from /lib/libpthread.so.0
# #2 _L_mutex_lock_82
from /lib/libpthread.so.0
# #3 __pthread_mutex_lock
at pthread_mutex_lock.c line 81
# #4 segv_redirect
at ../../../evolution/shell/main.c line 528
# #5 <signal handler called>
# #6 *__GI___libc_free
at malloc.c line 3596
# #7 IA__g_free
at ../../../glib/glib/gmem.c line 190
# #8 IA__g_ptr_array_free
at ../../../glib/glib/garray.c line 394
# #9 exchange_get_folder_info
at ../../../evolution-exchange/camel/camel-exchange-store.c line 771

It seems you've right, the gnome-2-28 sources are showing that the crash point is on line
> 	if (camel_stub_marshal_eof (exch->stub->cmd))
thus the stub is most likely NULL.

There is a downstream bug report about the same
https://bugzilla.redhat.com/show_bug.cgi?id=545133
which was invoked when the exchange server was unreachable.

I tried to reproduce this, but I failed. It doesn't want to crash to me. After a bit more investigation it seems the evolution-exchange-storage crashed for some reason, just between this line and a line above it, which is trying to connect to it. It's pretty unlikely, but obviously can happen. I added a test for Non-NULL value there, as a workaround, because this code doesn't exist in actual 2.29.5 development version.

Created commit 09caf93 in eex gnome-2-28 (2.28.3+)

It'll claim the evolution should be restarted, instead of crashing itself. The proper way might be to get why evolution-exchange process crashed and fix that.