Yes. Crashes here as you mentioned. (shell ok, popen not)

======= Backtrace: =========
/lib/tls/i686/cmov/libc.so.6(__fortify_fail+0x48)[0x20e008]
/lib/tls/i686/cmov/libc.so.6[0x20d040]
/lib/tls/i686/cmov/libc.so.6[0x20c36a]
/usr/lib/pd-extended/extra/flatspace/popen.pd_linux[0x77abeb]
pdextended(pd_typedmess+0x1fc)[0x80b613c]
======= Memory map: =======
(too big for posting... if it is useful i can attach it.)

Ubuntu karmic rt 32 bits
Pd version 0.42-5extended-20100530
compiled 09:02:05 May 30 2010



--
Pedro Lopes
contacto: jazz@radiozero.pt
website: http://web.ist.utl.pt/Pedro.Lopes