A quick mod to show the ordered items on PayPal side.
Please check these posts:
X-Cart 4.5.x. (Updated)
X-Cart 4.4.x. (Updated)
X-Cart 4.3.x. (Updated)
X-Cart 4.4.1 users should also apply the DIFF.patch.txt
Note: Gift certificate support has been added; incorrect order total in certain tax configurations issue has been fixed.