i'm using eclipse wtp

Build Type	:	Integration
Build Name	:	3.1
Stream	:	R3.1
Build Date	:	Thu, 2 Apr 2009 -- 04:46 (UTC)

1. download parts...
• 
  

  No.	Components	File Name
  1.	Eclipse Platform (Platform, JDT)	eclipse-SDK-3.5M6-win32.zip
  2	Web App Developers	wtp-I-3.1-20090402044606.zip
  3	EMF v2.5 Runtime Minimum executable code	emf-runtime-2.5.0M6.zip
  4	EMF XSD v2.5 Runtime Minimum executable code	xsd-runtime-2.5.0M6.zip
  5	Graphical Editing Framework (GEF)	GEF-SDK-3.5.0M6.zip
  6	Data Tools Platform (DTP) (required only for EJB or JPT development)	dtp-sdk-1.7.0M6-200903160500.zip

  
  
2. unzip
1. Eclipse Platform (Platform, JDT)
2. Web App Developers
3. EMF v2.5 Runtime Minimum executable code
4. EMF XSD v2.5 Runtime Minimum executable code
5. Graphical Editing Framework (GEF)
6. Data Tools Platform (DTP) (required only for EJB or JPT development)