$mbox = imap_open("{your.imap.host}","username","password",OP_HALFOPEN)   
or die("can't connect: ".imap_last_error());    
$name1 = "phpnewbox";  
$name2 = imap_utf7_encode("phpnewböx");    
$newname = $name1;    
echo "Newname will be '$name1'<br>\n";    
# мы создадим новый mailbox "phptestbox" в вашей папке inbox,  
# проверим его статус после создания и удалим его для восстановления  
# вашего inbox в первоначальном виде    
if(@imap_createmailbox($mbox,imap_utf7_encode("{your.imap.host}INBOX.$newname"))) {  
$status = @imap_status($mbox,"{your.imap.host}INBOX.$newname",SA_ALL);  
if($status) {  
print("your new mailbox '$name1' has the following status:<br>\n");  
print("Messages: ". $status->messages )."<br>\n";  
print("Recent: ". $status->recent )."<br>\n";  
print("Unseen: ". $status->unseen )."<br>\n";  
print("UIDnext:". $status->uidnext)."<br>\n";  
print("UIDvalidity:". $status->uidvalidity)."<br>\n";    
if(imap_renamemailbox($mbox,"{your.imap.host}INBOX.$newname","{your.imap.host}INBOX.$name2"))

{  echo "renamed new mailbox from '$name1' to '$name2'<br>\n";  $newname=$name2;  } 
else {  print "imap_renamemailbox on new mailbox failed: ".imap_last_error()."<br>\n";  }  } 
else {  print"imap_status on new mailbox failed: ".imap_last_error()."<br>\n";  }  
if(@imap_deletemailbox($mbox,"{your.imap.host}INBOX.$newname")) {  
print "new mailbox removed to restore initial state<br>\n";  } 
else {  print"imap_deletemailbox on new mailbox failed: ".implode("<br>\n",imap_errors())."<br>\n";  }    } 
else {  print"could not create new mailbox: ".implode("<br>\n",imap_errors())."<br>\n";  }    
imap_close($mbox);