I'm trying to generate Java classes from several specific XSD's with xjc. Those schemas have some definitions in common, so they import a number of common XSD's. In particular, they can include from zero to all of the common XSD's. 
I'd like to generate all classes from an specific XSD to a specific package, but keeping the generated classes for the common schemas in a common package, so they don't get repeated for each specific schema in the source tree.
I've learnt that custom bindings can be used to specify packages on a per-schema basis, with for instance:
<jxb:bindings schemaLocation="common1.xsd" node="/xsd:schema">
    <jxb:schemaBindings>
        <jxb:package name="mypackage.commonclasses"/>
    </jxb:schemaBindings>
</jxb:bindings>
I've got the following structure:
schemas
| - common
| | - common1.xsd --> XSD with common types #1
| | - ...
| | - commonN.xsd --> XSD with common types #N
| | - commonBindings.xjb --> Defines package "mypackage.commons" for common*.xsd
| - specific1
| | - specific1.xsd --> Includes ../common/common{1-N}.xsd
| | - specific1.xjb --> Defines package "mypackage.specific1" for specific1.xsd
| - specificN
| | - specificN.xsd --> Includes only ../common/common1.xsd
| | - specificN.xjb --> Defines package "mypackage.specificN" for specificN.xsd
It all works fine with:
xjc -b schemas/specific1
    -b schemas/common 
    schemas/specific1/specific1.xsd
It generates the classes for specific1.xsd in mypackage.specific1 and the common classes in mypackage.commons. But when I try to generate the classes for specificN, xjc throws the following error: 
[ERROR] "file:/drive/dir/schemas/common/common1.xsd" is not a part of
 this compilation. Is this a mistake for "/drive/dir/schemas/common/commonBindings.xjb"?
  line 2 of file:/drive/dir/schemas/common/commonBindings.xjb
I get this error repeated for every common XSD not imported in any specific xsd.
Is there any way I can make xjc ignore the bindings in commonBindings.xjb that aren't used in the XSD I'm generating the classes for?
Or, am I aiming in the wrong direction by using this approach, and should be, for instance, using annotations in the specific xsd? I'd like to avoid modifying the schemas if possible.