[libvirt] building error

[Wen Congyang]

When I build libvirt, I meet the following error message
sometimes:

make[4]: Entering directory `/home/wency/rpmbuild/BUILD/libvirt-0.9.11/docs'
  GEN    libvirt-api.xml
  GEN    libvirt-qemu-api.xml
  GEN    html/index.html
./libvirt-api.xml:2450: parser error : AttValue: ' expected
    <function name='virConnectDomainEventDeregister' file='libvi
                                                                ^
./libvirt-api.xml:2450: parser error : attributes construct error
    <function name='virConnectDomainEventDeregister' file='libvi
                                                                ^
./libvirt-api.xml:2450: parser error : Couldn't find end of Start Tag function line 2450
    <function name='virConnectDomainEventDeregister' file='libvi
                                                                ^
./libvirt-api.xml:2450: parser error : Premature end of data in tag symbols line 1129
    <function name='virConnectDomainEventDeregister' file='libvi
                                                                ^
./libvirt-api.xml:2450: parser error : Premature end of data in tag api line 2
    <function name='virConnectDomainEventDeregister' file='libvi
                                                                ^
unable to parse ./libvirt-api.xml
make[4]: *** [html/index.html] Error 6
make[4]: *** Waiting for unfinished jobs....

If I rebuild it without anything change, the building will success.