I'm using Axis 1.7.1 and found an issue using fixed values in WDSL and the ADB Codegenerator.
Basically when one fixed value/attribute exists, all attributes are treated as fixed attributes. This means, when setting the value on a non-fixed attribute, it set be seen as null (but set) and causing an exception once used to send to server.
I've attached a simplified WSDL.
I've looked in the ADB Codegen code, and IMHO the issue seems to be in SchemaCompiler where the code says:
// register the fixed value if present
if (xsElt.getFixedValue() != null)
The setFixed seems to be too broad, and maybe it can be changed into something following the registerNillableQName-flow, e.g. registerFixedQName(xsElt.getQName()).