Upgrading 1.5 to 1.5.1.2?

I’ve searched but I keep coming across 1.5.1 to 1.5.2 posts. My question is this…

Can I upgrade straight from 1.5 to 1.5.1.2 and if so – where is the definitive text explaining the process?

I’ve just installed a ‘test’ instance seperate to my main blog (which is 1.5) by downloading and installing a 1.5.1.2 version. When I’m happy with new setups etc. i want to upgrade my main site.

Thanks in advance for any advice / links etc.

c0y0te