Perhaps the clutch isn't completely disengaging. Are you certain that you're pushing the clutch in completely? Sometimes a warped clutch will be difficult to shift.
Synchro's are going bad inside the trans, should only be an issue while moving.
Heat shield on your exhaust system?
There are several things that can cause your 2005 Jeep manual transmission to shift hard between first and second gear. The most common cause is a malfunctioning shifting fork.
You can search the Internet to download a Jeep Wrangler owner's manual for free. You can also try contacting Jeep directly for a copy of the manual.
The 2002 Jeep Wrangler has a 5-speed manual.
The 2011 Jeep Wrangler has a 6-speed manual.
The 2009 Jeep Wrangler has a 6-speed manual.
The 2012 Jeep Wrangler has a 6-speed manual.
The 2006 Jeep Wrangler has a 6-speed manual.
The 2014 Jeep Wrangler has a 6-speed manual.
The 2003 Jeep Wrangler has a 5-speed manual.
The 2004 Jeep Wrangler has a 5-speed manual.