I think this is a dumb rule, so I would loophole the shit out of it.
If you can't technically solicit sales here, solicit traffic. Get people interested in your art, and link back to outside sites. Anytime you can post examples of your work, include a link to your commission info on other sites, preferably in tow with other links to your work. This would include sharing your portfolio, showing off recent art work, anything you get to share that could serve as a sample, make sure leave a link to your blog or website with it. Promote yourself in every other way to get people clicking so that eventually they will see your commission info.
Edit: Also maybe adding to your page description that questions are welcome, or something to that extent, welcoming people to message you personally. Then they can ask about your commission info if they're interested, without you outright mentioning you take commissions.