I have a problem with Borland C++Builder 6.

The problem comes when i try to run a program with it:

[Linker Error] Unresolved external 'WinMain' referenced from C:\PROGRAMFILER\BORLAND\CBUILDER6\LIB\C0W32.OBJ

What does that mean?
I have tried the same code in another compiler, and that worked just fine.