suid application fails to call execv
 

Want to setup web server so that where cgi stub/fastcgi stub will be running as root when web server instance runs as normal non privilege user say webservd. I set ownership of fastcgistub
directory to webservd and ran chmod 4755 on fastcgistub executable (owned by root). I have entered dependent library path into /etc/ld.so.config
and ran ldconfig.
While processing fastcgi request I get stub connection failure. From strace and also through debugger I see following problem:-

fastcgi stub has forked a child process. But It is failing to call execv. While debugging found all the required parameters are correct. It is same when suid is not set and web server works fine.
Even I can execute that command from command line. What could be the problem.

Following the same process I can run it successfully on solaris using crle command for global linking.

I tested on linux 2.4.21-9 and linux 2.6.9-67, it fails in both.

What could be the problem? Please help.

Regards
Ron

N.B. Checked /etc/fstab file systems are default, nosuid or user option are not present.