if ( bIn != null ) {
list = bIn.getExtensibilityElements();
for ( int i = 0 ; list != null && i < list.size() ; i++ ) {
Object obj = list.get(i);
if( obj instanceof MIMEMultipartRelated){
MIMEMultipartRelated mpr=(MIMEMultipartRelated) obj;
Object part= null;
List l= mpr.getMIMEParts();
for(int j=0; l!= null && j< l.size() && part== null; j++){
MIMEPart mp = (MIMEPart)l.get(j);
List ll= mp.getExtensibilityElements();
for(int k=0; ll != null && k < ll.size() && part == null;
k++){