Module development and code questions

Hi,
I searched (probably with the wrong words ;) ) but didn't find an answer to my question:
http://drupaldocs.org/api/head/function/arg says "Avoid use of this function where possible, as resulting code is hard to read. Instead, attempt to use named arguments in menu callback functions.See the explanation in menu.inc for how to construct callbacks that take arguments."
Where can I find the explanation or an example?

Thanks

Ralf

I've searched and read the docs, but I'm not seeing an answer. As far as I can tell, the pager doesn't hold onto the sort order of the table. Sorting works fine, paging works fine, but after choosing a sort order you can click on a pager like (next, etc) and the sorting is gone. Is there something I need to do to keep the sort order around? Looking at the pager code, it looks like it just doesn't bother with it. Should I hack the pager code or is there a better way?

When I create content, for example a story, where does is text from the "Abstract" input field used? I don't find it anywhere.
Thanks for your help.

I followed the instructions for installing the massmailer module, including changing the permissions of phplist/bin/phplist to 0755 but cannot send mail and am getting the following error:

You do not have the php command line executable in your system path
and it cannot be located in /usr/bin or /usr/local/bin.
Please edit the modules/massmailer/engines/phplist/bin/phplist file to correct this.

Any help would be great.

Thanks!

Jeremy

Help I am getting a "warning: mail() [function.mail]: SMTP server response: 501 5.5.4 Invalid Address" error when I try to submit a form from the feedback form. I am using the feedback module.
I have a valid email address in my default email.
I do not have "Validate Senders Email Address" checked.
I am running the website off of my own server. My other email functions work. Individuals who sign up are able to get their emails.

Any help would be greatly appreciated.

Mattso

I've installed the TinyMCE Editor and source code according to instructions and using phpMyAdmin. It works perfectly on my Drupal testsite located on a apache server that i run as localhost. However I get this error: