Co-founder with non-voting shares

I have an offer on a table to join this really exciting venture at 50/50 split as a tech co-founder but the original founder insists on issuing me non-voting shares. He worries that he will loose control of the company when we bring in the investors. He wants to maintain at least 51% of voting power after we raise Series A to have an upper hand over investors. Of course we can write protective clauses to bring back the voting power of my shares at the time of sale or Series B but is this enough to cover my butt?

Do I really care about voting power having complete control over the technical aspect of the product until we exit? Is this a healthy engagement, and what should I be worried about?

I think he doubts your decision making skills, or he is a control freak, or he only wants your money, or he doesn't know how to do business since he's already creating a bad working environment.

If the business is 50/50 on the cash, it must be 50/50 on the responsibilities. After all who will be making the decisions for the business? What if decisions taken by him are wrong?

There are other ways of dealing with the control issue than issuing non-voting shares -- consider a voting agreement, for example.