install via SSH, login to root
now type in SSH

# apt-get update
# apt-get upgrade
# apt-get install curl php5-curl

NEXT STEP
Now login via webmin, point to PHP Configuration, if you dont know, just type ‘php’ in search box and press ente.

now, open php configuration, edit it manually
find this line

just remove a semicolon ; sign

then save it.