"Illegal character in path"

Just had this error (elasticsearch 1.0.1), don't recall seeing it before:

java.net.URISyntaxException: Illegal character in path at index 29:
/cache/11_/seg0/index12450141[12450141].ts

Should I be concerned?

--
You received this message because you are subscribed to the Google Groups "elasticsearch" group.
To unsubscribe from this group and stop receiving emails from it, send an email to elasticsearch+unsubscribe@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/elasticsearch/34bb0d6a-598a-4ae7-9fa1-200e51da92a2%40googlegroups.com.
For more options, visit https://groups.google.com/groups/opt_out.