"function lower(integer) does not exist" error using Hibernate

Issue

INFO  [STDOUT] Hibernate: 
    select
        exoshellmo0_.category_id as category1_97_,
        exoshellmo0_.category_editor as category2_97_,
        exoshellmo0_.category_image as category3_97_,
        exoshellmo0_.category_meta_description as category4_97_,
        exoshellmo0_.category_meta_keywords as category5_97_,
        exoshellmo0_.category_url as category6_97_,
        exoshellmo0_.child_category_id as child7_97_,
        exoshellmo0_.content_category_name as content8_97_,
        exoshellmo0_.edit_lock as edit9_97_,
        exoshellmo0_.module_id as module18_97_,
        exoshellmo0_.user_roles_id as user19_97_,
        exoshellmo0_.expires as expires97_,
        exoshellmo0_.inherit_template as inherit11_97_,
        exoshellmo0_.ip_address as ip12_97_,
        exoshellmo0_.last_update as last13_97_,
        exoshellmo0_.page_template as page14_97_,
        exoshellmo0_.parent_category_id as parent15_97_,
        exoshellmo0_.post as post97_,
        exoshellmo0_.visible as visible97_ 
    from
        public.exoshell_mod_content_manager_categories exoshellmo0_ 
    where
        lower(exoshellmo0_.category_editor) like (lower(?)||'%')
00:35:22,651 WARN  [JDBCExceptionReporter] SQL Error: 0, SQLState: 42883
00:35:22,651 ERROR [JDBCExceptionReporter] ERROR: function lower(integer) does not exist
00:35:22,669 ERROR [viewhandler] Error Rendering View[/admin/adminconsole.xhtml]
javax.faces.FacesException: javax.el.ELException: /mods/exoshellcontentmanager/ExoshellModContentManagerCategoriesList.xhtml @28,92 rendered="#{exoshellModContentManagerCategoriesList.resultList.size lt 1}": Error reading 'resultList' on type com.domain.exoshellcms.session.ExoshellModContentManagerCategoriesList_$$_javassist_161
  ...
Caused by: javax.el.ELException: /mods/exoshellcontentmanager/ExoshellModContentManagerCategoriesList.xhtml @28,92 rendered="#{exoshellModContentManagerCategoriesList.resultList.size lt 1}": Error reading 'resultList' on type com.domain.exoshellcms.session.ExoshellModContentManagerCategoriesList_$$_javassist_161
     at com.sun.facelets.el.TagValueExpression.getValue(TagValueExpression.java:76)
     at javax.faces.component.UIComponentBase.isRendered(UIComponentBase.java:390)
     ... 82 more
Caused by: javax.persistence.PersistenceException: org.hibernate.exception.SQLGrammarException: could not execute query
     at org.hibernate.ejb.AbstractEntityManagerImpl.throwPersistenceException(AbstractEntityManagerImpl.java:637)
     at org.hibernate.ejb.QueryImpl.getResultList(QueryImpl.java:74)
     ... 83 more
Caused by: org.hibernate.exception.SQLGrammarException: could not execute query
     at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:67)
     at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:43)
     at org.hibernate.loader.Loader.doList(Loader.java:2223)
     at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2104)
     at org.hibernate.loader.Loader.list(Loader.java:2099)
     at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:378)
     at org.hibernate.hql.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:338)
     at org.hibernate.engine.query.HQLQueryPlan.performList(HQLQueryPlan.java:172)
     at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1121)
     at org.hibernate.impl.QueryImpl.list(QueryImpl.java:79)
     at org.hibernate.ejb.QueryImpl.getResultList(QueryImpl.java:65)
     ... 117 more
Caused by: org.postgresql.util.PSQLException: ERROR: function lower(integer) does not exist
     at org.postgresql.core.v3.QueryExecutorImpl.receiveErrorResponse(QueryExecutorImpl.java:1592)
     at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:1327)
     at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:192)
     at org.postgresql.jdbc2.AbstractJdbc2Statement.execute(AbstractJdbc2Statement.java:451)
     at org.postgresql.jdbc2.AbstractJdbc2Statement.executeWithFlags(AbstractJdbc2Statement.java:350)
     at org.postgresql.jdbc2.AbstractJdbc2Statement.executeQuery(AbstractJdbc2Statement.java:254)
     at org.jboss.resource.adapter.jdbc.WrappedPreparedStatement.executeQuery(WrappedPreparedStatement.java:255)
     at org.hibernate.jdbc.AbstractBatcher.getResultSet(AbstractBatcher.java:187)
     at org.hibernate.loader.Loader.getResultSet(Loader.java:1787)
     at org.hibernate.loader.Loader.doQuery(Loader.java:674)
     at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:236)
     at org.hibernate.loader.Loader.doList(Loader.java:2220)
     ... 125 more