In JkDefrag page:".... Note: This will not defrag system files such as the pagefile. To do that see the "see also" chapter for a link to Pagedefrag, a free utility by Microsoft Technet (formerly SysInternals)...."
I have reproducible problems with PageDefrag on my laptop. PageDefrag hangs on: Defragmenting C:\pagefile.sys. On my 2 PC's however, the PageDefrag program works fine, but I have uninstalled PageDefrag too :-)