The fruit of any action is of the same quality as the action itself. So indeed this infers that asking to have the same pay as a male colleague, or any colleague is in itself greed and that the fruit born from it would be of a similar type.

The Buddha I believe recommended that you never talk about the Kamma of another as it is usually just a way to hide a value judgement of someone else. Instead we should focus on what Kamma we take and therefore the type of fruits we'll experience in the future.

If this interests anybody - this is an excellent book on the subject: https://www.google.co.uk/url?sa=t&rct=j&q=&esrc=s&source=web...