In cases where ABL refers to fixed-array parameters, only the Doc/Lit WSDL style/use format represents the fixed size of the array; the RPC/Encoded and RPC/Literal formats represent all arrays as unbounded. Therefore, when using either of the RPC WSDL style formats, the developer must know the size of each array parameter that is expected. The WSA returns a SOAP fault if the array sizes do not match.
For details and examples of how WSDL represents arrays, see
Understanding WSDL Details.