[Snow]

Hi all,
I've been on this forum for a wee bit, and have posted with this same problem and have been trying to correct with a trainer here in Edmonton. I've been trying to get her into obedience classes (she's had all Petsmart classes - maybe a mistake, I realize this now!) but have been running into problems getting her into formal classes. The trainer that I picked is quite good, but the problem being that I don't think Isis can get into classes until she gets over this dog aggression that she seems to have developed recently. I am sure that some of you have had this problem before....
When I take her on walks, as soon as she sees another dog she loses it, and is the stereotypical snarling bad Rottie that we have all heard about. HELP! I need to correct this behaviour, soon! She is not an aggressive dog in general, she loves our new addition (a pug) and they play (supervised) to no end! She is awesome, but this problem is recurrent - has been happening for approx 8 mos (surprisingly the same amount of time we got our new pug...). I am pretty sure that this behaviour may be a protective instinct as she treats our pug like a puppy.
The other training places that I called before deciding on this one all were leery of her - perhaps because she is a Rottie or the word "aggression" - I don't know. I just feel that no one wants to take her on - but she is a super good dog, just this one recurrent problem.
I will keep pushing getting her into classes but it seems that no one really wants to take her with her "aggression" problem. But it isn't really an aggression problem, I think I need help to train her!!
HELP!
Any advice? I have been working with her from what the trainer suggested with her private classes but would really like to be able to get her into formal classes!!!!