Hi,
There should not be any problem of changing the directory location. Are you doing upgrade and is this happening while upgrade is in progress.
Are you also facing similar kind of validation errors:
012-08-22 05:31:28,347 WARN [domain.schema.SchemaBootstrap] [main] Schema validation found 81 potential problems, results written to: /opt/alfresco402/tomcat/temp/Alfresco/Alfresco-PostgreSQLDialect-Validation-Pre-Upgrade-alf_-8177759383561323090.txt
2012-08-22 05:31:28,425 WARN [domain.schema.SchemaBootstrap] [main] Schema validation found 14 potential problems, results written to: /opt/alfresco402/tomcat/temp/Alfresco/Alfresco-PostgreSQLDialect-Validation-Pre-Upgrade-avm_-3052080491422848160.txt
2012-08-22 05:31:28,453 WARN [domain.schema.SchemaBootstrap] [main] Schema validation found 28 potential problems, results written to: /opt/alfresco402/tomcat/temp/Alfresco/Alfresco-PostgreSQLDialect-Validation-Pre-Upgrade-jbpm_-7762514199473028451.txt
Thanks,