The government has the power to put people into prison not so much as punishment to the individual, but as protection for the rest of society from the prisoner's (probable) future wrongdoings. So, the government only takes your rights away when you are likely to exercise those rights at the expense of others.
That said (and having never been in prison myself), I suspect that being in prison has the ability to separate you so far from society that being given the opportunity to further participate/influence it is probably a bad idea. Just a thought. Anyway, I don't think felons, specifically, should be allowed to vote in any form of societal government.
