I downloaded and installed (in my Mandrake 9.1) Mono 1.0 RPMs from the mono project web site. I downloaded the RedHat 9 RPMs since there is no dedicated version for Mandrake 9.X (or 10.X). I had no problems with this, as I have never had problems downloading and installing RedHat RPMs in Mandrake. I managed to satisfy all dependencies, even needed to download a couple of updated packages from the mandrake web site and from http://rpm.pbone.net/
The problem is that, after installing almost everything (Core, Cairo Dependencies, Mono and Microsoft Stacks, Wine updated, Data and MonoDevelop) when I run /usr/bin/mono or /usr/bin/mcs (for example)
I receive this message:

mono: error while loading shared libraries: libmono.so.0: cannot handle TLS data

Does anyone understand this message or have a clue of what might be happening?

Thanks in advance.

Yes buddy this is a problem due to Thread Local Storage (TLS), and as the threads are changes not too long ago so this problem occurs. I think downloading the latest version of MONO and glibc will solve your problem.

Not Just mono
Also download latest version of glibc

Don't upgrade your glibc, this will *not work* and you are most likely to destroy your install.

Instead upgrade your distribution. I am afraid this is the only sane way to deal with this error. I had no idea Mono was using ELF TLS, it surprises me actually ....

BTW you need a distro that supports NPTL or use RPMs built for your particular distribution.

Or alternatively you may have the "wrong" CPU.

What is NPTL?
I have never had problems with RPMs for RedHat in my distro (Mdk 9.1) if they are from a relatively recent RedHat version (except of course, dependencies problems, which I solve downloading the packages needed)
I haven't found Mono RPMs for Mandrake 9.x or 10.x

And what do you mean with "the 'wrong' CPU" ??

I am already downloading glibc and a bunch of updates it required for other packages.
I'll tell you when I'm done.

Thanks for the feedback you guys.

Wrong as in an i386 rather than 486/586/686