hi,
Using Arch 64 here.
I installed the lpsolve package, and replaced /opt/mule/data/lib/liblpsolve55j.so with the 64 bit version, as you directed.
I skipped the part about creating a link, things seem to be working fine.
I use sudo. if you don't, then you probably already know how to translate to/from sudo and # directions. don't forget to do so.
So, the Arch 64 version of this:
0. Install planetmule via the AUR.
http://aur.archlinux.org/packages.php?ID=33457$ sudo yaourt -Sy planetmule
1. Run planetmule as root, to allow it to update on it's own.
2. Verify that it no longer works by trying to play it.
3. Download the lpsolve .zip.
$ wget http://downloads.sourceforge.net/project/lpsolve/lpsolve/5.5.0.15/lp_solve_5.5.0.15_java.zip
3. unzip it
$ unzip lp_solve_5.5.0.15_java.zip
4. back up the 32-bit liblpsolve55j.so
$ sudo mv /opt/mule/data/lib/liblpsolve55j.so /opt/mule/data/lib/liblpsolve55j.so-backup
5. replace that one with the version you just downloaded, the 64 bit one.
$ sudo cp ~/lp_solve_5.5_java/lib/ux64/liblpsolve55j.so /opt/mule/data/lib/liblpsolve55j.so
6. verify that planetmule now works.
if it doesn't, i suppose try installing the lpsolve package from the repos and creating a link as puzzud suggested. package name is "lpsolve", in the "extras" repo.