Is auto trans fluid OK in a manual gearbox?

Hi all,
 I'm having a few issues with the gearbox in my '93 Camry ( 4 cyl SDV10). 
When I checked the gearbox oil today, I found that it had Automatic 
transmission fluid in it, not the 75-90 oil which Toyota recommends.
Looking 
over the service history (Done by Toyota), they have listed that they put 
auto trans fluid in it. Twice.
On top of that, I had a CV done by another mechanic recently, who topped
it 
up with gear oil at the time. So I think I now have a mixture of Auto
trans 
fluid and gear oil in my gearbox.

So, is is OK to run a manual gearbox with auto transmission fluid in it?
Is 
it going to cause me a problem?