FishEye failed to index Mercurial repository if one of commits have no commit message

FishEye cannot index mercurial repository and after error occurred it starts from beginning. And this activity looks like an endless loop.

Error message is

Repository index failed due to error com.cenqua.fisheye.rep.RepositoryClientException: com.atlassian.fisheye.dvcs.handler.DvcsProcessException: Error while communicating with VCS: com.atlassian.fisheye.dvcs.handler.DvcsProcessException: Error while communicating with VCS: com.atlassian.utils.process.ProcessException: While executing: "hg --config extensions.felog=/usr/lib/yandex/crucible/python/hg/hgfelog/hgfelog.py --config ui.verbose=false felog 81973987ae521a51f9cc2a26a0e21f8fc8c8d8cb -p -m " com.atlassian.utils.process.ProcessException: java.lang.RuntimeException: Match failed: string [P:df6c2a1d335e33d5a6a4f36e282921a82f6e9203], pattern [M:(.*)] java.lang.RuntimeException: Match failed: string [P:df6c2a1d335e33d5a6a4f36e282921a82f6e9203], pattern [M:(.*)]

I checked hgfelog.py and specified (81973987ae521a51f9cc2a26a0e21f8fc8c8d8cb) commit. And realize what match failed because FE waiting for commit message ([M:(.*)]) but receive parent commit ([P:(.*)]). And this commit dosn't contain commit message at all.