I am using xfdesktop-4.3.90.2 on solaris x86. I get a SEGV when I start
xfdesktop

Reading libscf.so.1
Reading libuutil.so.1
Reading libresolv.so.2
Reading libexpat.so.0.5.0
Reading libXrandr.so.2
Reading xfce4_desktop_menu.so
t@2 (l@2) signal SEGV (no mapping at the fault address) in g_thread_pool_thread_proxy at 0xfe4a57ff
0xfe4a57ff: g_thread_pool_thread_proxy+0x00b7:  pushl    0x0000000c(%esi)
dbx: read of 8 bytes at address fc0fc000 failed -- Error 0
dbx: attempt to read frame failed -- cannot derive frame pointer
0xfd3a4a70: _lwp_start       :  addl     $0x00000004,%esp
(dbx) where
current thread: t@2
dbx: read of 8 bytes at address fc0fc000 failed -- Error 0
dbx: attempt to read frame failed -- cannot derive frame pointer
  [1] g_thread_pool_thread_proxy(0x80c4250), at 0xfe4a57ff 
  [2] g_thread_create_proxy(0x80c5cf8), at 0xfe4a4383 
  [3] _thr_setup(0xfd2a2400), at 0xfd3a481f 
=>[4] _lwp_start(), at 0xfd3a4a70 
  [5] 0x0(), at 0xffffffffffffffff 


I have the core file, and this is easily reproduce able.