While trying to run MEME I was getting an error:

You must define environment variable MEME_DIRECTORY

I could run the program from the command line with no options, and it wold print the help message and exit, but if I tried to run it with any parameters, it printed the message above and quit.

So I defined the environmental variable as follows:

MEME_DIRECTORY=/path/to/meme
export MEME_DIRECTORY

and now the program runs. I guess you just have to set the variable to the pace where meme is installed, not the bin dir holding the program, but the main meme dir just above it.