rfcomm: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/bin/rfcomm - from package: bluez

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/rfcomm - from package: bluez

You may install the required package with command apt-get install {package}

Error in other languages:
rfcomm: bevel nie gevind nie
rfcomm: comandă negăsită
rfcomm: comando não encontrado
rfcomm: commande introuvable
rfcomm: command not found
rfcomm: käsku ei ole
rfcomm: không tìm thấy lệnh
rfcomm: komanda nerasta
rfcomm: Kommando nicht gefunden.
rfcomm: kommandot finns inte
rfcomm: komut yok
rfcomm: nie znaleziono polecenia
rfcomm: níor aimsíodh an t-ordú
rfcomm: no se encontró la orden
rfcomm: no s'ha trobat l'ordre
rfcomm: opdracht niet gevonden
rfcomm: parancs nem található
rfcomm: perintah tidak ditemukan
rfcomm: príkaz nenájdený
rfcomm: příkaz nenalezen
rfcomm: команда не найдена
rfcomm: командата не е открита
rfcomm: 命令找不到
rfcomm: コマンドが見つかりません