Problems with the 'EXECL' QNX command

It goes like this.

We have an application that we have built with QNX4.24. We have used
this application for several years running with photon1.12 and
X-windows. Do to the updating of QNX we have decided to move to the
newer QNX4.25 and photon1.14. I have made minor modification to the
directory structure and change some define names. I have tested the
newly created code on the QNX4.24/photon1.12 and it work just fine. On
the QNX4.25/photon1.14 system the code fails. During debug I was able
to determine the location of the failure is at the QNX command
‘execl(PATH, application, arg1, arg2, NULL)’. I have been able to debug
up to this point. Once this point is reached the an attempt to start the
new application is made and the debug session is finished. The display
screen goes blank and nothing else happens. I have to do an
‘ALT-DEL-SHIFT-BACKSPACE’ TO GET BACK TO A WORKING SYSTEM. In the
4.24/1.12 system the application continue correctly, in the 4.25/1.14
system the application appears to lock up. I have compared the data
being loaded prior to the ‘execl’ command on both systems. The data is
the same in both.

I guess at this point with our testing I’m not sure where to go. I guess
the first question would be, have QNX made modification to the ‘execl’
function? Or have QNX made modifications to the OS that would cause this
type of problem? Could I have a setup problem with some part of QNX4.25
that needs to be made? Is there any further testing I could do to prove
out where the error may lye? Is there more information I can give you?

If you could help me out here that would be great.

Hope to hear from someone soon.