4 way ligation avoided !!!!!!

[John Brennand]

how about some lateral thinking .....

why not drop a short oligo pair into the nco/hind cut vector which 
contains additional sites eg Not, Sfi, etc that are not elsewhere in 
the vector or your pcr product, then use one of those in your 3' 
primer.

we actually do this a lot - providing your oligos are short <30 and 
purified - it always works and we rarely get any clones with the 
wrong oligo sequence.

john