We present JABERT, the first BERT model pretrained specifically for historical Judeo-Arabic texts. We demonstrate that JABERT outperforms Arabic and multilingual models on the downstream task of Judeo-Arabic homograph disambiguation. Furthermore, in order to test the latter, we have curated and annotated the first Judeo-Arabic homograph test set. We release both JABERT and the Judeo-Arabic homograph test to the public for unrestricted use.