reading Data(Serial)

Hi im writting a program to send and receive data from a com port(wirless appliction) for several baudrates.
By cables everithing is OK but without it i m getting lots of garbage instead of DATA-unless i m sending "U" Chars (I didnt use overlap)
What is wrong?(ATTACHED FILE)
[283 byte] By [gadi] at [2007-11-18 1:35:26]