%requires macro error when build in redhat6

[Hasan Yavuz]

Hello all

I have an error when build rpm in redhat 6:
error: line 16: Dependency tokens must begin with alpha-numeric, '_' or 
'/': Requires: %{REQUIRES}

Here the entry in my spec file:
Requires: %{REQUIRES}

Here the entry in my rpmmacros file:
%REQUIRES       expect gawk python rcs screen tar wget

All these values are working fine with Redhat 5 and redhat 4.

Does anyone have an idea?

Thanks