** The files are "owned" by "nobody." **
Files created by a script will often have permissions set that way. In such a case deleting them can be done by programming another script to do the deleting.
I didn't realize that is what you were asking.
** If the code could be changed to write the files with the correct owner rather than "nobody", that would probably solve the problem? **
That could easily be done just by running the script through cgiwrap or running Perl suEXEC (ask your host). Either way, all files created by your scripts have your ownership.
JMO
Dan O.
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