Partnership - late registration

I have taken on a new partnership client in the last week. The partners have registered as self employed, but not the partnership. 

Consequently the partnership has not been issed with a UTR.

Because of this not only can I not file a partnership tax return but I suspect that I won't be able to file the individuals returns without the partnership number. The period during 2010-11 was very short and probably loss making so I was planning to file the tax returns for the individuals without partnership pages but with a note in the white space saying we are awaiting the partnership reference.

Presumably when the partnership return is issued I will have three months to file it. I will then be able to amend the individual partners returns.

Will following this course of action avoid penalties?