The PIX wil translate the source port as follows (no way to change it):
- If the source port is TCP/UDP 1-511, then the PIX will PAT the SRC address to one in that range.
- If the source port is TCP/UDP 512-1023, then the PIX will PAT the SRC address to one in that range.
- If the source port is TCP/UDP 1024-65535, then the PIX will PAT the SRC address to one in that range.
The only way to make sure the PIX uses a number greater than 1023, is to make the originating host use a source port greater than 1023.