Might be interesting to see whether you have the problem with VBS as well. Try the following two scripts to see if you get the same problem:

ietest.vbs:

set oShell = CreateObject("WScript.Shell")
oShell.Run "iexplore.exe http://uk.yahoo.com", 1, TRUE
[download]

ietest.pl:

use Win32::OLE;

$obSh = Win32::OLE->new('WScript.Shell') or die "Can't start Shell err
+or=", Win32::OLE->LastError();
$obSh->run("iexplore.exe http://uk.yahoo.com", 1, 1) or die "Failed to
+ launch IE, error = ", Win32::OLE->LastError();
[download]

Have to wonder why you are using WSH rather than just shelling out using backticks?

Gordon