Bug 30005 Can't create linked source folder in new java project wizard [build path]
Build: I20030122 1) Open the new java project wizard 2) Enter a name, hit next 3) Click "Add Folder" on the "Source" tab. -> dialog comes up that doesn't have an option to create a new folder 4) Click cancel. Click "Browse" next to the output folder field -> this dialog allows you to create a new folder (even a linked folder) 5) Click cancel. Finish the wizard. 6) Open the java build path property page 3) Click "Add Folder" on the "Source" tab. -> now the dialog allows you to create a new linked folder. It should allow you to do this from the wizard.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/wizards/buildpaths/BuildPathsBlock.java
IResource res= fWorkspaceRoot.findMember(path);
		if (res != null) {
			
			if (res.getType() == IResource.FILE) {
				fOutputFolderStatus.setError(NewWizardMessages.getString("BuildPathsBlock.error.InvalidBuildPath")); 
				return;
			}
		}	
		fOutputFolderStatus.setOK();
		updateBuildPathStatus();
	}
		
	private void updateBuildPathStatus() {
		List elements= fClassPathList.getElements();
		IClasspathEntry[] entries= new IClasspathEntry[elements.size()];
	
		for (int i= elements.size()-1 ; i >= 0 ; i--) {
			CPListElement currElement= (CPListElement)elements.get(i);
			entries[i]= currElement.getClasspathEntry();
		}
		
		IJavaModelStatus status= JavaConventions.validateClasspath(fCurrJProject, entries, fOutputLocationPath);
		if (!status.isOK()) {
			fBuildPathStatus.setError(status.getMessage());
			return;
		}
		fBuildPathStatus.setOK();
	}