finding type of function arguments with gdb

Question

I'm working on reversing some private functions in CoreTelephony for iPhone. Reversing objC is no biggie, but I can find the type of the arguments for example of _CTServerConnectionCreate. if I break at _CTServerConnectionCreate and use "info args" it will fail because no symbol table info is available :( If I switch to that frame and use "info frame" I get

Stack level 0, frame at 0x2fffe94c:
 pc = 0x3380807c in _CTServerConnectionCreate; saved pc 0x15fe0
 called by frame at 0x2fffe9d8
 Arglist at 0x2fffe944, args: 
 Locals at 0x2fffe944, Saved registers:
  r4 at 0x2fffe938, r5 at 0x2fffe93c, r6 at 0x2fffe940, r7 at 0x2fffe944,
  r8 at 0x2fffe934, lr at 0x2fffe948, pc at 0x2fffe948

but that doesn't help me much.

Do you have any idea about finding the type of function arguments?