I can take care of the Persian translations + designing the required RTL CSS + making sure the templates bundled with 1.7.1+ will support RTL correctly.
Current (temp) Persian translations use non-standard characters (according to the Persian Academy); I will fix that too.
Just let me know if there is a SVN repo you're using, and I'll send patches to you.
I'm also planning on adding an addon (and before that, making such an addon possible by modifying the core) to use different calendar systems (like Jalali calendar, used in Iran) instead of the default Gregorian calendar. (Many projects support such calendars either natively or through addons; examples are Wordpress and MediaWiki).
By the way... I'm also interested in helping with the development and bug-fixing of Pixelpost. So if you want a helping hand there, just let me know.