My first guess would be that the file doesn't have executable permissions. What user are you running it as? If the file is owned by the user or a group the user is in, if there are no executable permissions for the user, then even if 'all' has executable permissions, the user still won't be able to run it.
So for instance, if it is owned by the user Nagios, but there the file doesn't have executable permission for user, then you will get that error, even if file is executable by all / others:
[kbrandt@kbrandt-opadmin: ~/scrap] ls -l true.pl <24252@6:17>
-rw-rw-r-x 1 kbrandt kbrandt 603 2009-04-14 13:17 true.pl
[kbrandt@kbrandt-opadmin: ~/scrap] ./true.pl
zsh: permission denied: ./true.pl
The same goes for groups. If a file were owned by the user 'Joe' and the group 'Nagios', and user kbrandt who is a member of group Nagios tried to run it, if the group column doesn't have executable permission, kbrandt won't be able to run it.
Update after long Comment Thread:
Have you tried Recompiling the plug-ins on that machine?
thats it! the files get copied from
another (intel machine) automatically
by opsview on this one! compiling
plugins from source worked