SQL & PL/SQL

Hi all, i have a procedure called proc_send_mail, the procedure obviously, send a mail using utl_smpt. I use that procedure in many clients and just in one of them, i got this error (ORA-29279: SMTP permanent error: 503 Issue MAIL FROM: command before RCPT T).

Here is my code:

recStat := utl_smtp.helo(c, vServidor);
vStatus := nvl(vStatus,'') || to_char(recStat.code) ||' '|| recStat.text;
dbms_output.put_line('Status:'||vStatus);

recStat := utl_smtp.mail(c, p_address_from);
vStatus := nvl(vStatus,'') || to_char(recStat.code) ||' '|| recStat.text;
dbms_output.put_line('Status3:'||vStatus);
dbms_output.put_line('p_address_from:'||p_address_from);
dbms_output.put_line('p_address_to:'||p_address_to);

utl_smtp.rcpt(c, p_address_to);
vStatus := nvl(vStatus,'') || to_char(recStat.code) ||' '|| recStat.text;
dbms_output.put_line('Status2:'||vStatus);

-- This is the message
vMensagem := 'MIME-Version: 1.0' || chr(13) || chr(10);
vMensagem := vMensagem ||'From: '|| p_mail_from ||' <'|| p_address_from ||'>'|| chr(13) || chr(10);
vMensagem := vMensagem ||'Subject: '|| p_subject || chr(13) || chr(10);
vMensagem := vMensagem ||'To: '|| p_mail_to ||' <'|| p_address_to ||'>'|| chr(13) || chr(10);
vMensagem := vMensagem ||'Reply-To: '|| p_address_from || chr(13) || chr(10);

So, i call:

- utl_smtp.helo
- utl_smtp.mail
- utl_smtp.rcpt -----> in this i have trouble

anyone can help me? I check the mail from and mail to, and they are correct.

P.S: Sorry, my english is too bad.