$("#login_form").submit(function(event)

I need to pass the word 'event' to the jquery function only for firefox for it to work?

WTF? All my functions need changing then?

The event argument (which could be named e, evt, or hocupokus) is optional, actually, all parameters are optional in javascript.

Can you elaborate on what your issue is? What is happening?

commented: This explanation was correct -I hate to see it downvoted +9

Need the 'event' keyword only for firefox all the other web browsers seem ok.

Can you please expand on your example code, (...not enough data to process...)

There has to be an alternative approach to the problem, probably not as convenient - but at least, one that will walk you across.

p.s.:
Yes it is true that to be able to use it, (refer to the currrent event),- supplying the event argument-name in the function in Firefox is mandatory, (since like forever). And it always has to be the first argument on the arguments namespace.

Firefox is mandatory, (since like forever)

Indeed. However, I've just found this out from triall and error. Luckily I tested it in firefox but it took ages for me to uncover this quirk.

Will know this for next time. Thanks for your repy and time.

So why am I downvoted, if you please care to explain?
Thanking me this way for giving you the most
accurate explanation posssible, - expecially when taking in account the fact that your question was far from clear.
What is this?

I've just found this out from triall and error.

And no, you didn't! - I told you so.
Because there's absolutely nothing else to explain here You my friend should have marked this thread Solved.