Admin login with Opera

I have encountered strange behaviour when trying to login to admin using Opera.

Having (finally) managed the upgrade to 1.36, I attempted to login to admin to start the customisation process. I know the username, and password are correct, as they are needed during the database upgrade process. Each attempt, (and there were many), returned me to the login page.

Some time was devoted to changing passwords, logging in as an alternative user, doing the Admin admin thing etc. All with the same result.

Out of ideas, I tried IE (kept only to check for viewing problems etc). Surprisingly, login worked at the first attempt. I have downloaded Firefox 2, and login is a painless process also.

Having a viable alternative to IE, I am not too much concerned with this issue, but I am a little puzzled as to why this is happening?

System info:
Opera version is 9.02 build 8585
Win xp pro sp2

I've never gotten Zen to work well with Opera. I don't know what it is...but the zen cart administration console just doesn't like it.

The strange thing is, it is only since the update the Opera ceased to work. Previously, I had no problems

I haven't got an upgraded Admin to test on but a fresh install works fine for me with Opera. Are you using SSL? Shared or dedicated?

At the moment, the upgraded shop is on localhost, undergoing customisation etc, so no SSL.

As I mentioned previously, I can use firefox, so I don't have a problem as such, just thought it was unusual?