Subqueries in mySQL

Hello,
I have this problem. I wrote an app in ASP and SQL Server and ended having to use mySQL because that's all that's available on the remote server. The thing is, I had some queries written that simply won't work in mySQL and I can't find what is wrong with them. They worked perfectly in SQL Server and they aren't even complex. Then, mySQL is not running any subqueries even in the simplest SELECT * from A where x IN (SELECT x from B) form. It tells me there's an error 1064: "You have an error in your SQL syntax".
What am I doing wrong?
My original query was:
select distinct clients.client_id, client_name, mat_name, end_date, budget_id, materials.mat_id
from materials, matsteps, clients
where materials.mat_id=matsteps.mat_id
and materials.client_id=clients.client_id
and step_id not in (select step_id from matsteps where prop_enddate is null)
and (prop_enddate>=getdate() or getdate()-prop_enddate<=7)
order by end_date

I replaced getdate() by CURDATE() but the real problem is the subquery because if I delete that row, the query works. Any help will be appreciated.

What version of mysql? I don't believe subselects are implemented until version 4. For dates, I usually use NOW(), incidentally.

It's the latest version, I just downloaded it two days ago and got the production version 4.0.18 for Windows... The CURDATE() function works perfectly.

Last I checked, you needed mysql 4.1.1a-alpha, at least, to use subqueries.

Though it is alpha, it has been rock solid for my purposes so you might want to try before you pass judgement.