When loading module liquibase.xml files, only the omod and main jar files are searched as per this line, this line, and this line. This leads into a problem where liquibase.xml files in conditionally loaded jar files are not found. I discovered this while working on
TRUNK-5338 where i move the liquibase.xml file from omod/src/main/resources/liquibase.xml → api-pre2.2/src/main/resources/liquibase.xml in order for the module to create the conditions table only when running on openmrs platform versions before 2.2 as per this commit: https://github.com/openmrs/openmrs-module-emrapi/commit/27e37f3e9344954a2aa1959657d30489557ec9c4
This was a result of platform 2.2 introducing a conditions table which conflicts with the one already found in the emrapi module.
The same bug goes for the sqldiff.xml file but i did not get bothered fixing it because it is deprecated in favor of liquibase.xml.