How to parameterize transaction timeout without disabling xsd validation?

[d_cavestro]

Given the following spring batch configuration snippet

<chunk reader="myReader" writer="myWriter" commit-interval="${my-batch-tx-commit-interval}" />
<transaction-attributes isolation="DEFAULT" propagation="REQUIRES_NEW" timeout="5" />

I'd like to express even the transaction timeout though an appropriate palceholder, resolved to an integer value.
The problem is that the xsd specifies an integer type for that attribute, so if I would use something like

<transaction-attributes isolation="DEFAULT" propagation="REQUIRES_NEW" timeout="${my-batch-tx-timeout}" />

my xml wouldn't be valid.
I know I could disable xsd validation as per http://stackoverflow.com/questions/4...on-in-spring-3 (provided that it's not so easy when you start your application context from web.xml), but it seems somewhat strange having a textual commit-interval and a numeric transaction timeout (see http://www.springframework.org/schem...-batch-2.1.xsd ).