[chris_dcosta]

There is another approach which is equally as effective given you signed this some time ago.

You can ask the company to confirm that you are allowed to work on the outside project and that they do not consider it to be a conflict of interest.

My partner for example is working for a large corporation, and in her contract it expressly forbids being a director of another company. I wanter her to be the director of one of mine for family reasons, and she obtained a written confirmation that this was agreeable to her employer.

This effectively changed - or rather updated - the terms on which she signed her employment. There's no reason why you could not do this too.

As long as what you are doing is not within the general scope of activities of your employer then a release like this is not that difficult to obtain.