Find attached BPEL, WSDL and XSD files. The bpel contains an assign that has the
input message type variable mapped to output message type variable. There are
multiple issues with this and should not be allowed in the mapper. The issues being:

1. The input variable has one part whereas the output variable has two parts,
hence they cannot be mapped.
2. If you delete the variable level mapping and try to map the parts, the mapper
does not complains and allows this to happen. This is not valid also, as the
parts are not of the same xsd type. One is xsd string simple type, other is
simpletype defind with restriction (user defined simple type).

The rule of thumb is the mappings should only be allowed for the type compatible
nodes on both the sides. Here is the snippet from the spec (section assignment)

"The <assign> activity copies a type-compatible value from the source
("from-spec") to the destination ("to-spec"), using the <copy> element."

I am also doing to file another bug with validation, to invalid such BPEL that
contain such mappings (user could hand code bpel, without using mapper).