opera bug in openbsd 5.1 release with Abort Trap message

[daemonfowl]

Hi everybody !
:-)
I know OpenBSD hackers disapprove of using closed source binaries and Theo once said the Team is an open source community .. there are a few features in Opera (like widgets .. etc) which I like/need .. anyway , I installed OpenBSD 5.1 stable and got this bug :
On reboot Opera fails to start , leaving the shell with a message " Abort Trap".
Unless I remove the package and install the port anew , it won't start even after deleting the whole ~/.opera folder ..
I'd be glad to learn what that message means and which trap is aborted .. is it a tech message peculiar to opera or does it extend to other more software ?
By the way, this bug doesn't exist in OpenBSD current .. :-)

$ sudo sysctl kern.version
kern.version=OpenBSD 5.1 (GENERIC.MP) #188: Sun Feb 12 09:55:11 MST 2012
    deraadt@i386.openbsd.org:/usr/src/sys/arch/i386/compile/GENERIC.MP

Thanks very much !