pointing stains

[mpaton2009]

hi
i have a front garden wall that is old stock brick and needs repointing
i simply cannot avoid getting some mortar on the brick work due to the small gaps, and although i soaked the brick before starting and try my best to get any off it dries like a horrible white film all over the brickwork which is invisible when wet
i bought some GeoChem brick cleaner and this did bugger all to get it off

what can i do to get rid of this and more importantly, stop it from happening in the first place?

it looks bloody awful and i'm seriously at the point of considering rebuilding the wall!!!

 

[foxhole]

White on brickwork is salts washed out by rain , only time will cure when they are all rinsed out, wetting the brickwork only helps the salts travel out.

 

[mpaton2009]

I don't think it's efflorescence, just mortar stains (as when the mix has gone off there is a fine dust that remains on the surface, which just seems to stay on the brick no matter what I do to get it off and then when it goes off leaves a nice film of hard mortar dust)