Adobe(Omniture) Sitecatalyst - Variable limits CheatSheet
The following character limits are for languages whose characters are one byte.For Asian languages like Japanese which constitute multiple bytes per character, the limitations will differ -probably less characters
- PageName / s.pageName - 100 characters
 - Server / s.server - 100 characters
 - Hierarchy / s.hier -Maximum of 255 characters
 - Traffic variables / s.props - 100 characters
 - Conversion Variables / s.evars - 255 characters
 - events / s.events - unlimited But remember the s.events variable cannot contain any spaces and should contain only valid event name