Postgres JDBC-hibernate Problem

We have upgraded from PostgreSQL 8.4.3 to PostgreSQL 9.1.4 and we are
getting the following errors when attempting to auto-gen schema DDL.

Old Configuration:

WEB-INF/lib/postgis-jdbc-1.3.3.jar,
WEB-INF/lib/postgis-stubs-1.3.3.jar,
WEB-INF/lib/postgresql-8.3-603.jdbc4.jar,

New Configuration:

Tomcat 7
Java 1.6.0_35

Spring Framework 3.1.2, hibernate sessionFactory via
'org.springframework.orm.hibernate4.LocalSessionFactoryBean'
Hibernate Core 4.1.6.Final
Hibernate Spatial 4.0.M1
PostgreSQL JDBC4 9.1-901
postgis-jdbc 1.5.2
c3p0 0.9.1.2

auto DDL update phase fails with Exception:

11:59:23,736 [localhost-startStop-1] INFO java.sql.DatabaseMetaData:120 -
HHH000262: Table not found: SOME_TABLE
11:59:23,738 [localhost-startStop-1] ERROR
org.hibernate.tool.hbm2ddl.SchemaUpdate:245 - HHH000299: Could not complete
schema update

org.hibernate.MappingException: No Dialect mapping for JDBC type: 1852802018
(**Changes at each webapp startup)
at org.hibernate.dialect.TypeNames.get(TypeNames.java:76)
at org.hibernate.dialect.TypeNames.get(TypeNames.java:99)
at org.hibernate.dialect.Dialect.getTypeName(Dialect.java:299)
at
org.hibernate.spatial.dialect.postgis.PostgisDialect.getTypeName(PostgisDial
ect.java:247)
at org.hibernate.mapping.Column.getSqlType(Column.java:227)
at org.hibernate.mapping.Table.sqlCreateString(Table.java:481)
at
org.hibernate.cfg.Configuration.generateSchemaUpdateScript(Configuration.jav
a:1140)
at
org.hibernate.tool.hbm2ddl.SchemaUpdate.execute(SchemaUpdate.java:212)
at
org.hibernate.tool.hbm2ddl.SchemaUpdate.execute(SchemaUpdate.java:178)
at
org.hibernate.internal.SessionFactoryImpl.<init>(SessionFactoryImpl.java:492
)
at
org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1746)
at
org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1784)
at
org.springframework.orm.hibernate4.LocalSessionFactoryBuilder.buildSessionFa
ctory(LocalSessionFactoryBuilder.java:242)
at
org.springframework.orm.hibernate4.LocalSessionFactoryBean.buildSessionFacto
ry(LocalSessionFactoryBean.java:372)
at
org.springframework.orm.hibernate4.LocalSessionFactoryBean.afterPropertiesSe
t(LocalSessionFactoryBean.java:357)
at
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory
.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1514)
at
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory
.initializeBean(AbstractAutowireCapableBeanFactory.java:1452)
at
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory
.doCreateBean(AbstractAutowireCapableBeanFactory.java:519)
at
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory
.createBean(AbstractAutowireCapableBeanFactory.java:456)
at
org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(Ab
stractBeanFactory.java:294)
at
org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSi
ngleton(DefaultSingletonBeanRegistry.java:225)
at
org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(Abst
ractBeanFactory.java:291)
at
org.springframework.beans.factory.support.AbstractBeanFactory.getBean(Abstra
ctBeanFactory.java:193)
at
org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolv
eReference(BeanDefinitionValueResolver.java:322)
at
org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolv
eValueIfNecessary(BeanDefinitionValueResolver.java:106)
at
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory
.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1360)
at
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory
.populateBean(AbstractAutowireCapableBeanFactory.java:1118)
at
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory
.doCreateBean(AbstractAutowireCapableBeanFactory.java:517)
at
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory
.createBean(AbstractAutowireCapableBeanFactory.java:456)
at
org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(Ab
stractBeanFactory.java:294)
at
org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSi
ngleton(DefaultSingletonBeanRegistry.java:225)
at
org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(Abst
ractBeanFactory.java:291)
at
org.springframework.beans.factory.support.AbstractBeanFactory.getBean(Abstra
ctBeanFactory.java:193)
at
org.springframework.beans.factory.support.DefaultListableBeanFactory.preInst
antiateSingletons(DefaultListableBeanFactory.java:609)
at
org.springframework.context.support.AbstractApplicationContext.finishBeanFac
toryInitialization(AbstractApplicationContext.java:918)
at
org.springframework.context.support.AbstractApplicationContext.refresh(Abstr
actApplicationContext.java:469)
at
org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicat
ionContext(ContextLoader.java:383)
at
org.springframework.web.context.ContextLoader.initWebApplicationContext(Cont
extLoader.java:283)
at
org.springframework.web.context.ContextLoaderListener.contextInitialized(Con
textLoaderListener.java:111)
at
org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:
4791)
at
org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:
5285)
at
org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at
org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:9
01)
at
org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877)
at
org.apache.catalina.core.StandardHost.addChild(StandardHost.java:618)
at
org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:963)
at
org.apache.catalina.startup.HostConfig$DeployWar.run(HostConfig.java:1600)
at
java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:441)
at
java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
at java.util.concurrent.FutureTask.run(FutureTask.java:138)
at
java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.ja
va:886)
at
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:9
08)
at java.lang.Thread.run(Thread.java:662)

Dialect specification in hibernate.properties is:
hibernate.dialect=org.hibernate.spatial.dialect.postgis.PostgisDialect

Any assistance will be greatly appreciated.

thanks
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