htaccess mod rewrite to php

I apologize for posting a question regarding htaccess files...but I'm desperate...Nobody can help me...

http://httpd.apache.org/docs-2.0/mod/mod_rewrite.html
http://www.engelschall.com/pw/apache/rewriteguide/
After reading through these...I still can't get this darn simple mod rewrite rule to work. Can anyone help.

Trying to have this... ex. www.mydomain.com/123 redirect to www.mydomain.com/in.php?link=123

I got it working with the following...

RewriteEngine on
RewriteRule ^([0-9]+) /in.php?link=$1

but every time I change the regular expression it goes all down the crapper...don't know why.

I tried these and none work...only the [0-9]
(.+)
(.*)
([A-Za-z0-9]+)
([a-z0-9]+)

Thanks for your time,
Dave

Unsuccesfull threads...

interesting...
I hadn't tried just using [A-Z] rather than [a-z]...
You would never guess what happened.

I get this error on my apache log file.

RewriteRule: cannot compile regular expression '^([a-z]+)'

Yet it goes perfectly through ^([A-Z]+)

why the hell is it having problems with a lowercase list. Any ideas...