Solaris

Your query is already answered by others here, I am sure your onsite guy or someone senior should have access to that console or a engineer would be in datacenter with that sun keyboard.

Get them to do Stop+a, you get to single usermode, copy over the files. and reset the password using the CD/DVD rom

/tmp gets cleared when you do a reboot, you should have checked it first

1. This is not a server in a remote datacentre. Its my brother's box. If that were my client's box.. I would have received my bye-bye letter by now. (Believe me, when I explained this scenario to my senior, he was like as if I had done the unthinkable.)
2. It doesn't have a console.
3. I disabled stop+a keystroke. That means, I cannot get the ok> prompt.
But, my sa200 doc says that stop+a, even if disabled, will work during booting. Will test it once I get home.
3. The /tmp dir is not a tmpfs. It is a part of /.. hence will be avaialable across reboots.

I'm afraid you are also mistaken here. As a SVR4 Unix, Solaris is removing everything under the /tmp directory at boot time. On Solaris 10 and newer, this is done by the svc:system/rmtmpfiles:default service which is enabled by default. Older release had an rc file for the same purpose.