What software package did you purchase? If it is a chat server that allows multiple users to login, it would seem to me that it is running a persistent process on the server. This type of application is sometimes forbidden by DH, depending on the amount of system resources they consume, so that might be something to look into.
From the wiki:
What is your persistent (background) process policy?
We define persistent/background processes as any unix user's command running non-interactively. That is, it runs while you aren't actively sitting there interacting with it through a shell window.
Firstly, we reserve the right to kill any user process on a shared server without warning or prior notification at our discretion.
We don't just do this capriciously though! We do this if the process is in any way adversely affecting the smooth functioning of your shared server. Of course if you have a dedicated server you can run whatever (LEGAL) processes you'd like, you should just be prepared for the consequences they may have on your machine.
- IRC-related persistent processes of any kind (including, but not limited to, bots, bouncers, etc.) are STRICTLY PROHIBITED, and are in violation of our TOS (http://www.dreamhost.com/tos.html).
- BitTorrent-related processes are not allowed.
- Streaming Audio or Video servers of any kind are not allowed on shared hosting servers.
- Running programs via cron is allowed provided you don't use excessive system resources.
If you want to set something up and have any questions just ask our friendly tech support team, they don't bite.