I'm currently migrating our ssl setup from apache to nginx, but I've hit a roadblock. In our apache config we have SSLInsecureRenegotiation on
due to some incompatibility issues with safari. I can't find the equivalent command in nginx. Is there one?
You should look into the viability of just losing that particular option. As the name suggest it's insecure!
Nginx currently (since 0.8.23) does not do TLS renegotiation at all, anyway.
Also, while I realize you seem to be in a position where compatibility with broken clients seems to be more important than security (unfair argument: why are you using TLS, if you're going to poke holes in it?), I suggest checking your site with Qualys SSL Labs's SSL Server Test.