Problems to install a mod when FTP required

[Yur1]

We have hosted our forum on VPS platform,so now when I trying to install any package/mod it requires to compile the FTP data,I compile it and proceed,it takes some times to respond and when and when it respond nothing hapens and I have to do all over again-as if I had not done anything!
How i can load a mod ,and how solve this
Thank you for help

[Orangine]

what your Apache log says?
are you using Suhosin or similar?