用ant里的plugins编译插件报错

报的错误:
[trycatch] Caught exception: org.apache.jasper.JasperException: org.apache.jasper.JasperException: XML parsing error on file /WEB-INF/web.xml
[echo] Error building plugin: dbaccess. Exception:
[echo] D:\WorkSpace\openfire_jg\build\build.xml:1483: org.apache.jasper.JasperException: org.apache.jasper.JasperException: XML parsing error on file /WEB-INF/web.xml
openfireHome:
[echo] No custom config here

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