Most probably a juniper Secure Access SSL VPN appliance. I was administrating one too when heartbleed was "made public".

Luckily we were not running the latest Version Tree of the firmware so we were still on an older openssl version.

I dont think Juniper Devices have more or less culnerabilities than other vendors. Its highly developed stuf (chasing technical advances, bringing new firmwares every other month).

You just shouldnt use .0-1 Versions of new Release Trees like with every Vendor...

And for Heartbleed: Nearly Everyone based on linux/Openssl was affected somehow.