PC to Mac (tiger) filename truncation problem


I am at an office making the switch from PC to Mac!
we are having problems loading files from the PC server to Mac (tiger) - when files come across they are trucated w/ ˜ at the end of the name. this is major problem b/c the defining part of the names in our file system are at the end of the name.... all of our files look the same now!

am I not viewing the files properly? how do I prevent this from happening?