我正在尝试安装 Apantana Eclipse 插件，但是我收到此错误消息：
Cannot complete the install because one or more required items could not be found.
Software currently installed: GWT Designer Editor 2.6.0.r36x201206111227 (com.google.gdt.eclipse.designer.editor.feature.feature.group 2.6.0.r36x201206111227)
Missing requirement: Apache Xerces-J 2.9.0.v201101211617 (org.apache.xerces 2.9.0.v201101211617) requires 'bundle javax.xml [1.3.4,2.0.0)' but it could not be found
Cannot satisfy dependency:
From: GWT Designer UiBinder Support 2.6.0.r36x201206111227 (com.google.gdt.eclipse.designer.UiBinder 2.6.0.r36x201206111227)
To: bundle org.eclipse.wb.core.xml 0.0.0
Cannot satisfy dependency:
From: GWT Designer Editor 2.6.0.r36x201206111227 (com.google.gdt.eclipse.designer.editor.feature.feature.group 2.6.0.r36x201206111227)
To: com.google.gdt.eclipse.designer.UiBinder [2.6.0.r36x201206111227]
Cannot satisfy dependency:
From: WindowBuilder Core for XML GUI's 1.5.0.r36x201206111216 (org.eclipse.wb.core.xml 1.5.0.r36x201206111216)
To: bundle org.eclipse.wst.xml.ui 0.0.0
Cannot satisfy dependency:
From: Structured Source XML Model 1.1.503.v201102102045 (org.eclipse.wst.xml.core 1.1.503.v201102102045)
To: bundle org.apache.xerces [2.9.0,3.0.0)
Cannot satisfy dependency:
From: Eclipse XML Editors and Tools 1.1.103.v201101122108 (org.eclipse.wst.xml.ui 1.1.103.v201101122108)
To: bundle org.eclipse.wst.xml.core [1.1.500,1.2.0)
我尝试将 xerces（我希望我做对了）添加到类路径，但我仍然收到此错误消息。
System Config:
Win7 64bit
Eclipse HELIOS ver 3.6.2
Java 1.6.0_21.
我将不胜感激任何帮助/线索。
谢谢。