[RFI] octstr_recode

I'm trying to use the octstr_recode function to convert a MO message from UCS2 to
ISO-8859-1 or UTF-8

I was thinking in trying to recode to ISO-8859-1 if possible, otherwise convert to UTF-8
and set coding acordly.

I thought that if the text couldn't be translated to ISO-8859, 
octstr_recode (octstr_imm("iso-8859-1"), octstr_imm("UTF-16BE"), text)) would
return false and I could switch to 
octstr_recode (octstr_imm("utf-8"), octstr_imm("UTF-16BE"), text)

but the first recode converts my %06%4A to a ي and returns ok.

2002-03-05 18:04:51 [6] INFO: DAVI:Received message with coding 3
2002-03-05 18:04:51 [6] INFO: DAVI:Received unicode message -J-064A-
2002-03-05 18:04:51 [6] INFO: DAVI: recode to iso8859-1 -ي-2623313631303B-
2002-03-05 18:04:51 [6] INFO: Starting to service <&#1610;> from <my-number> to <short-number>
2002-03-05 18:04:51 [6] DEBUG: formatted text answer: <Go away>
2002-03-05 18:04:51 [6] DEBUG: message length 7, sending 1 messages

May I search for &#xxxx; in utf16-be to iso8859-1 and reject it, switching then to utf8 ??