Up until iPrint Client 5.68 bootup of Windows XP SP3 worked flawlessly.

Don't know about 5.69 FTF.

With iPrint Client 5.72 and 5.74 XP SP3 bootup hangs on some PCs (around 10% in our environment). They will not even do DHCP.
Power Off, Power On and then on almost all PCs the bootup will work normally and the problem disappears.
On one PC I had to Power cycle around 25 times until the bootup finally worked again.

The only component of iPrint that is loaded that early is %windir%\system32\drivers\nipplpt.sys. Which is the LPTx: redirector.

Please open a SR on this issue.
Thank you.