And fails with "abort: unknown revision".
This has occurred twice for me during hg svn push. In both cases, there is the now-remote revision and the local revision remains with an empty delta.
This did not occur on my mac, recently switched to ubuntu on a lenovo. Extension differences due to ubuntu defaults:
children churn convert fetch gpg imerge inotify patchbomb
It is not: Due to rebasing on new remote revisions during push. (1 was, 1 was not) Affected by time difference between local & remote changeset. (1 within a minute, one 21 hours later, timestamps on local/remote appear reasonable)