Java application launching an other using Runtime.exec()

I have a Gui java appication that starts an other Gui java application by this way:
Runtime.getRuntime().exec("java -classpath ....")
At first a MSDOS window appears.
Then the new Gui window is display only if i change the size of the first Gui wiindow several times !
I works on Windows NT with jre 1.2
Is somebody knows the reason why the Gui not appears automatically and how to do it ?
Thanks in advance.

Yes, using javaw do not open MSDOS window but my problem is still the same:
the window of the 2d Gui is displayed only if i change several ltimes the size of the 1st Gui window !
An other sign: if i close the 1rst Gui after the 2d is launched , the 2d Gui is displayed !
Nevertheless these two applications run in independent process ?
Have you an idea ?

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