Send mail via ABAP functions SO_NEW_DOCUMENT_SEND_API1

I’m working with the function SO_NEW_DOCUMENT_SEND_API1 in order to send e-mails through SAP. The sent e-mails arrived ok but the files attached (pdf type) present missing lines at the 65 character. Actually, the subsequent characters (such us 66) are moved to the next line. What I should do to avoid this error at the PDF document?