[TYPO3-Solr] Strange error message in catalina.out

[Dominique Feyer]

Hi,

Since the upgrade to the last version (2.8) of the solr extension, I 
have this kind of error message in the catalina.out log file:

SEVERE: org.apache.solr.common.SolrException: ERROR: 
[doc=3406cf9c497da2a5b418424322e64ee8b57ab894/tx_csdistribution_domain_model_movie/] 
Error adding field 'uid'=''

Any this change in TS since 2.2 ?

Bests,

Dominique Feyer