Ordernumber is increasing by two instead one

Hi there,

I had the following configuration. 2 numberseries one for the cnd one for the order:

 <bean id="orderCodeGenerator" class="de.hybris.platform.servicelayer.keygenerator.impl.PersistentKeyGenerator">
     <property name="key" value="${keygen.order.code.name}" />
     <property name="digits" value="10" />
     <property name="start" value="420000000" />
     <property name="numeric" value="true" />
     <property name="template" value="$" />
 </bean>

 <bean id="cartCodeGenerator" class="de.hybris.platform.servicelayer.keygenerator.impl.PersistentKeyGenerator">
     <property name="key" value="cart_code" />
     <property name="digits" value="10" />
     <property name="start" value="420000000" />
     <property name="numeric" value="true" />
     <property name="template" value="cart_$" />
 </bean>

 <bean id="commerceCartFactory" class="de.hybris.platform.commerceservices.order.impl.CommerceCartFactory">
     <property name="netGrossStrategy" ref="netGrossStrategy"/>
     <property name="keyGenerator" ref="cartCodeGenerator"/>
     <property name="modelService" ref="modelService"/>
     <property name="userService" ref="userService"/>
     <property name="commonI18NService" ref="commonI18NService"/>
     <property name="baseSiteService" ref="baseSiteService"/>
     <property name="baseStoreService" ref="baseStoreService"/>
     <property name="guidKeyGenerator" ref="guidKeyGenerator"/>
 </bean>

And cache size is set to 1: numberseries.cache.size.luckynumberseries=1

Unfortunately my configuration isn't working correctly, The order number will be always increased by two instead one. The cartcodegenerator on the other hand is working correctly... Does anybody know what I'm doing wrong?

Greetz