When using Liquibase keep in mind, that it is executing all sql commands directly via JDBC. So all non JDBC conform command will throw a error.
I know many DBMS have command line tools with special command sets (sqlplus or db2 cli are examples) but their extensions are not valid sql and can not be executed by liquibase. You either have to rewrite the sql files or change them in some kind of preprocessing (search and replace the suspect lines).