upgrading seo urls

Since upgrading to 1.3.0 the seo keywords i used in 1.2.9 don't work properly they either bounce back to the page from where i clicked on the sub catergory or show no products on the page. But if i change the seo keywords to something else they work.

I Was wondering if its possible to fix this, without having to do a fresh install as a lot of time has gone into research/adding of products ect.

i left an example here http://www.sixdecibels.co.uk/computers click on apple and watch it bounce back if i change the seo url it will go to the appropiate page with the products stated.

Also im not sure if this is related but typing anything after the backslash of our url takes you to our homepage, obviously this does not cause any major problems but is it related and should it do it?

Turns out it was to do with multiple entries with the same alias in the url_alias table. Some of these even refered to categories that didn't appear in the categories table.

Not sure how they got there or anything, and we haven't removed some of the spurious categories, but simply deleting the records with duplicate alias from url_alias has resloved the problem.