Is there a way with Storage Manager (or another product) to notify users when they are within a certain percentage of their Home Directory's quota?

I'm fairly new to Storage Manager and was looking through the guides and did not see anything jump out at me for this ability, so I apologize if this is referenced somewhere and I just missed it. If so please point me to the location.

The issue that I'm running into is this... I have my user's "Documents" folder directed to their home directory, and what frequently happens is that the GroupWise attachments folder fills up their quota, which causes them to panic and call help desk whenever they can't open an attachment, or save a document. I don't allow the home directories to grow, I have a number of people that would just exploit that with junk files, but what I would like to do is have an automatic notification get sent when they are within say 15% of their quota's capacity and then again at maybe 5%. Is there a way to do this?