ura3 mutant yeast strain grows on SD-uracil- - (Oct/11/2012 )
ı have a yeast strain (
two days ago
1) Your medium is not really ura-
2) Your yeast is not ura-
2a) A rare but possible mutation restored ura+ to your strain.
I'd vote for a contaminant ura+ strain, but check the medium with a verified ura- strain.