Let me begin by admitting that I am a newbie!  I followed the simple OsCommerce four step installation procedure from Fantastico.  When i go to log into the admin. area of OsCommerce...it's not letting me in as though I have the wrong password and/or username but I'm sure I'm using the correct one because I had them emailed to me.  When I asked for help from lunarpages they sent me a tutorial on how to reset the password via the htaccess file...I've done this several times with no success.  I've also tried setting the password via the password directory utility on Cpanel with no success.  I have searched for other articles on this issue and found several indicating that others have had this problem but really can't understand the solution. 

Any help would be greatly appreciated...and remember I'm a newbie so be as specific as you can.
Thanks in advance!

Lunarpages support kindly resolved this issue for me. 
They referenced this article:  http://forums.oscommerce.com/lofiversion/index.php?t293274.html

Also, it's important to note that php5 should be installed prior to installing the latest version of OsCommerce.

osCommerce does not require PHP 5. Release 2.2RC2 did accidentally include one or two PHP 5 functions, but Release 2.2RC2a included a fix for this (define replacement functions for systems not on PHP 5).