Partial template specialization based on "signed-ness" of integer type?

Given:

template<typename T>
inline bool f( T n ) {
  return n >= 0 && n <= 100;
}   

When used with an unsigned type generates a warning:

unsigned n;
f( n ); // warning: comparison n >= 0 is always true

Is there any clever way not to do the comparison n >= 0 when T is an unsigned type? I tried adding a partial template specialization:

template<typename T>
inline bool f( unsigned T n ) {
  return n <= 100;
}   

but gcc 4.2.1 doesn't like that. (I didn't think that kind of partial template specialization would be legal anyway.)