hi,
i think you're using deprecated API (ref. to Deprecated List (Web Dynpro runtime environment (Netweaver�2004S�SPS 09)) ).
com.sap.tc.webdynpro.progmodel.api.IWDModifiableBinaryType
Use IWDResource instead. More documentation see IWDFileUpload and IWDFileUpload.
- FileUpload and FileDownload: Data Transfer - Developing Java Web Dynpro Applications - SAP Library
- IWDResource
regards,
christian