Backtrace seen in issue #173684:

#0  0x01d37c01 in _int_malloc (av=0x1dfe820, bytes=129) at malloc.c:4030
#1  0x01d38e95 in _int_realloc (av=0x1dfe820, oldmem=0xa545b80, bytes=128)
    at malloc.c:4671
#2  0x01d3a0fc in *__GI___libc_realloc (oldmem=0xa545b80, bytes=128)
    at malloc.c:3494
#3  0x005a4de6 in IA__g_realloc (mem=0xa545b80, n_bytes=128) at gmem.c:168
#4  0x005b6e53 in g_string_maybe_expand (string=0x9dcc860, len=Variable "len" is
not available.
) at gstring.c:261
#5  0x005b70b2 in IA__g_string_insert_len (string=0x9dcc860, pos=39, 
    val=0x3412b4 "<searchrequest xmlns=\"DAV:\"><sql>\r\n", len=35)
    at gstring.c:490
#6  0x005b73e5 in IA__g_string_append (string=0x9dcc860, val=0xa52b660 "")
    at gstring.c:519
#7  0x0032b921 in e2k_context_search_start (ctx=0x9a949b0, op=0xa52b660, 
    uri=0x9aa3bb8 "http://zcarhxm1.ca.nortel.com/exchange/nstuyt/", 
    props=0x34537c, nprops=6, rn=0x9ab9800, orderby=0x0, ascending=1)
    at e2k-context.c:1795
#8  0x003172e3 in e_folder_exchange_search_start (folder=0x9aa81b0, 
    op=0xa52b660, props=0xa52b660, nprops=173192800, rn=0xa52b660, 
    orderby=0xa52b660 "", ascending=173192800) at e-folder-exchange.c:664
#9  0x00323328 in scan_subtree (hier=0x9aa6950, parent=0x9aa81b0, mode=2)
    at exchange-hierarchy-webdav.c:718
#10 0x003244e6 in exchange_hierarchy_scan_subtree (hier=0x9aa6950, 
    folder=0x9aa81b0, mode=173192800) at exchange-hierarchy.c:319
#11 0x0031b40b in exchange_account_rescan_tree (account=0x9a4e390)
    at exchange-account.c:340
#12 0x0806d3f7 in e_book_backend_exchange_start_book_view (backend=0x9a8b448, 
    book_view=0x9a6df20) at e-book-backend-exchange.c:1959
#13 0x0072a074 in e_book_backend_start_book_view (backend=0x9a8b448, 
    book_view=0x9a6df20) at e-book-backend.c:304