Is rotating between several referral buttons against the terms?

[Linda_A]

I am wondering whether anyone knows if it would be okay (within Google's terms, I mean) to use php (or something else) to rotate between several referral buttons?

I would like to try out more than just one type of referrals, but I don't really want to have more than one button showing at any give time.

[kaz]

i do similar without any problem. test, test, test.

[Linda_A]

Thanks. :)