unlink file rights problem

Hi there, I am trying to unlink a file which is inside a folder that is not writable to phps user "www". Of course this failes, but I need to find a solution for it. Backgroud is following: I have pure-ftpd installed where user directories get created by pure-ftpd. Unfortunatelly there seems to be a bug and pure-ftpd does only create the homedirectory folder in 750 mod. My PHP-Script scans this directories every x minutes and processes those files. Upon completinon those files should get deleted, but as the dir is not writable by the user www this failes. The dir looks like this: drwxr-x--- 2 ftpuser ftpgroup 4096 Jan 28 10:18 merlin/ files inside look like this: -rwxrwx--- 1 ftpuser ftpgroup 16868 Jan 28 10:20 test.xml* User www which executes php via cron is inside the group "ftpgroup". Any ideas? I am kind of lost with this one. Thank you for any help! Best regards, Merlin