The USB port detection functions in SymbianDeviceManager
On windows, it looks in an area of the registry, and for a specific driver string, which are only valid for Nokia phones.
On linux, it looks for ttyUSB0 and ttyUSB1. This is good for Samsung and Nokia (as long as you only the phone plugged in and no other usb serial devices), but SEMC has 4 USB ports rather than 2.
The USB port detection in the runonphone test tool is known to work for Samsung/Nokia on windows and linux.
SEMC is untested, it will probably work on windows but not linux.
(source in qt4.7:tools/runonphone/serenum*)
Probably a good approach would be to merge the port enumerators (getting samsung support in creator for free), then fix SEMC issues.