This is ide.log + description from customer. I'm not able to reproduce it. 
Maybe this one is related to issue #12541.

--------------------------------------------------------------
>Log Session: Sunday, July 29, 2001 5:43:26 PM EEST
>System Info: 
  Product Version = Forte(tm) for Java(tm), release 2.0, Community Edition 
(Build 1160)
  IDE Versioning = IDE/1 spec=1.1.0.1 impl=Build 1160
  Operating System = Windows 2000 Version 5.0 Running on x86
  Java Version = 1.3.1
  Java VM Version = Java HotSpot(TM) Client VM 1.3.1-b24
  Java Vendor = Sun Microsystems Inc.
  Java Vendor URL = http://java.sun.com/
  Java Home = e:\JDK13~1.1\jre
  Java Class Version = 47.0
  System Locale = en_US
  JIT = unknown or not used
  Home Dir = C:\Documents and Settings\killa
  Current Directory = e:\forte4j
  Forte for Java Home = E:\forte4j
  Forte for Java User Home = E:\forte4j
  System Directory = E:\forte4j\system
  CLASSPATH = E:\forte4j\lib\patches\core_patch.jar;E:\forte4j\l 
ib\patches\openide-compat.jar;E:\forte4j\lib\patch 
es\openide_patch.jar;E:\forte4j\lib\developer.jar; 
E:\forte4j\lib\openide.jar;E:\forte4j\lib\updater. 
jar;E:\forte4j\lib\ext\AbsoluteLayout.jar;E:\forte 
4j\lib\ext\icebrowserlitebean.jar;E:\forte4j\lib\e 
xt\javac.jar;E:\forte4j\lib\ext\jaxp.jar;E:\forte4 
j\lib\ext\jh.jar;E:\forte4j\lib\ext\parser.jar;E:\ 
forte4j\lib\ext\regexp.jar;E:\forte4j\lib\ext\serv 
let.jar;E:\forte4j\lib\ext\kenv.zip;E:\forte4j\lib \ext\ktools.zip;e:\JDK13~1.1
\lib\dt.jar;e:\JDK13~1 .1\lib\tools.jar
-------------------------------------------------- -----------------------------
[INFO] Loaded modules: org.netbeans.modules.clazz/1 (1.2.1/1160); 
org.netbeans.modules.html/1 (1.2.1/1160); org.netbeans.modules.httpserver/1 
(1.2.1/1160); org.netbeans.modules.icebrowser/1 (1.2.1/1160); 
org.netbeans.modules.image/1 (1.2.1/1160); org.netbeans.modules.properties/1 
(1.2.1/1160); org.netbeans.modules.text/1 (1.2.1/1160); 
org.netbeans.modules.usersguide/1 (1.2.1/1160); org.openidex.util/1 
(1.2.1/1160); org.netbeans.modules.autoupdate/1 (1.3.1.1/ffj2-65); 
org.netbeans.modules.debugger.core/1 (1.1.5.2/ffj2-65); 
org.netbeans.modules.applet/1 (1.2.1.2/ffj2-65); 
org.netbeans.modules.debugger.debug/1 (1.4.1.1/ffj2-65); 
org.netbeans.modules.debugger.jpda/1 (1.4.1.1/ffj2-65); 
org.netbeans.modules.editor/1 (1.4.1.2/ffj2-64); 
org.netbeans.modules.jarpackager/1 (1.2.1.2/ffj2-65); 
org.netbeans.modules.java/1 (1.2.1.2/ffj2-65); org.netbeans.modules.beans/1 
(1.2.1.1/ffj2-65); org.netbeans.modules.form/1 (1.2.1.2/ffj2-65); 
org.netbeans.modules.i18n/1 (1.2.1/1160); org.netbeans!
modules.javadoc/1 (1.2.1/1160); org.netbeans.modules.objectbrowser/1 
(1.2.1/1160); org.netbeans.modules.projects/1 (1.2.1/1160); 
org.netbeans.modules.utilities/1 (1.2.1/1160); 
org.netbeans.modules.vcs.cmdline/1 (1.3.1.2/ffj2-65); 
org.netbeans.modules.web.core/1 (1.1.3.1/ffj2-65); org.netbeans.modules.kjava/1 
(1.2/${buildnumber})
path="" :jsp: init
*********** Exception occurred ************
Sun Jul 29 17:44:06 EEST 2001java.awt.IllegalComponentStateException: component 
must be showing on the screen to determine its location
java.awt.IllegalComponentStateException: component must be showing on the 
screen to determine its location
        at java.awt.Component.getLocationOnScreen_NoTreeLock
(Component.java:1242)
        at java.awt.Component.getLocationOnScreen(Component.java:1216)
        at javax.swing.JPopupMenu.show(JPopupMenu.java:731)         
	at org.openide.awt.JPopupMenuPlus.show(JPopupMenuPlus.java:41)
        at org.netbeans.core.windows.MultiTabContainer$PopupMouseImpl.showPopup
(MultiTabContainer.java:1019)
        at org.openide.awt.MouseUtils$PopupMouseAdapter.mouseReleased
(MouseUtils.java:150)
        at java.awt.AWTEventMulticaster.mouseReleased
(AWTEventMulticaster.java:231)
        at java.awt.AWTEventMulticaster.mouseReleased
(AWTEventMulticaster.java:230)
        at java.awt.Component.processMouseEvent(Component.java:3715)
        at java.awt.Component.processEvent(Component.java:3544)
        at java.awt.Container.processEvent(Container.java:1164)
        at java.awt.Component.dispatchEventImpl(Component.java:2593)
        at java.awt.Container.dispatchEventImpl(Container.java:1213)
        at java.awt.Component.dispatchEvent(Component.java:2497)
        at java.awt.LightweightDispatcher.retargetMouseEvent
(Container.java:2451)
        at java.awt.LightweightDispatcher.processMouseEvent(Container.java:2216)
        at java.awt.LightweightDispatcher.dispatchEvent(Container.java:2125)
        at java.awt.Container.dispatchEventImpl(Container.java:1200)
        at java.awt.Window.dispatchEventImpl(Window.java:914) 
        at java.awt.Component.dispatchEvent(Component.java:2497)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:339)
        at java.awt.EventDispatchThread.pumpOneEventForHierarchy
(EventDispatchThread.java:131)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy
(EventDispatchThread.java:98)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:85)

OPERATING_SYSTEM: WIN2000
REPEATABILITY: Reproducible
EDITION_VERSION: ffj2.0
PROBLEM: Using multiDesk (http://www.techsuperior.com/products/index.html) to 
switch between virtual desktops, Forte's currently hidden windows (Explorer 
Window, Debugger Windows, Output Window) can become visible, when switching 
back to the desktop Forte is on. Then windows from different workspaces 
(Editing, Running, ...) are displayed at the same time. Hidden windows are 
displayed totally grey and cause IllegalComponentStateExceptions, when right-
clicked to bring up their context-menus.
JVM_VERSION: Java(TM) 2 Runtime Environment, Standard Edition (build 1.3.1-b24)


[FFJ CUSTBUG] *** this bug was reported by customer ***