Debian, backport and tsearch

I'm using etch.

I may upgrade to lenny in the not so far future if it becomes stable
at least not earlier than 3-4 months.

I'm in the need of tsearch but nothing has been written right now.

The available options I see are:
1) use the contrib module on 8.1
2) backport 8.3

Considering I'll upgrade to lenny ASAP[1] anyway which path would you
suggest me to follow?
I'd prefer to use backport.

If 1) could somebody point me to some good documentation about what
I'll have to be careful about once I'll have to move from
8.1+contrib tsearch to 8.3?

If 2) is there a detailed HOWTO to switch from etch 8.1 to backport
8.3?

[1] that doesn't mean as soon as lenny will be stable, but as soon
I'll be able to handle it.

thanks

--
Ivan Sergio Borgonovo
http://www.webthatworks.it