i still have no idea how this works.
say i have a level 9 fighter for example. if i wanted to dual class him to a fighter/mage, when i am going to level up next, click dual class? am i right so far? then i click on mage.
would my mage level progression be as slow as it would be as if i was goin g to continue as a fighter?
for example, say after i reached lvl 10 as a fighter. i had(for example) 100 000 xp and i needed 200 000 xp to get to lvl 11 as i faighter. if i was to dual class into a mage instead, would i still need another 100 000 xp to goto lvl 2 mage? or would i only need something trivial such a 2 000 xp?
sorry if that is confusing.

Check this Dual Classing FAQ.

I strongly suggest that you read the whole FAQ not just this. Also take a look at the patching section.

[ 12-30-2004, 06:38 AM: Message edited by: Xen ]

so you have to get another 100 000 xp before level 2 wizard is obtained

No, you would need 2500XP to become a L2 Wizard. 5000XP to become a L3 Wizard etc.

You cannot use any of your fighter abilities (i.e. THACO, weapon proficiencies) until your mage level surpasses that of your fighter level.

So your mage needs to advance through levels 1-11 using the mage experience chart before you regain the use of your L10 fighter abilities.

Clearer?

I have a different sort of dual-classing question, one that was not covered in the FAQ.

Say that you start as a fighter. At the start of the game, you have 89,000 XP and are a level 7 fighter, which is 36K XP short of the next level up.

Now say that you immediately decide to dual-class to some other class (which one is unimportant to this question). What happens to those "extra" 36,000 XP? Are they effectively lost? Are they transferred to your new class?

Correct me if wrong, but I think that they are transfered to your new class.

I think you start at 0 exp when you dual, no matter what.

[ 12-30-2004, 10:31 AM: Message edited by: bjorn ]

If (*IF*) you start at 0 XP when you dual, then it seems that the correct time to dual is immediately after a level up so that you lose the fewest possible XP.

OK. I've just verified that bjorn is correct. When you dual class, your XP in the new class is set to ZERO. Furthermore, you lose the excess XP in the old class.

I just ran a little test in BG2 where I created a human fighter with high enough stats to dual to a thief. After dualing to a thief, the XP in the new class was set to 0 and the XP in the old class was set to 64,500 IIRC. Nearly all of the excess XP was lost.

Therefore, my previous statement is correct. The best time (as in "minimum XP wasted") to dual is immediately after leveling up in the first class.

and the best time to level in in pure SoA is right at the start..

Now some people don't agree with this saying it's better to dual later and in some cases they are right, but it all depends on what you want..

If you've got ToB it's better to dual at higher level's for more bonuses, some people would suggest level 14 or so, others would say even higher.. But then it depends if you've got the XP cap remover which most people consider cheating.