Long term capital gains =~15% on stock sales. My pal says it only applies to Fed tax NOT state. I say wrong.

Told my bud that I got zinged on stock sales as I didn't pay long term cap gains tax (company was taken over and we were cashed out - didn't know at the time) so I'm not having to tak the hit on Fed AND state (CA) returns. He says I should ONLY be paying the Fed, not CA. I say I need to pay BOTH. Who's right?