Yes, you can, the easiest way is to just use the included binary that comes with the SDK and use system() and escapeshellarg() to call it. Make sure you check all the user data is valid.
PHP has a builtin Verisign package, but I never personally used it. I heard Versign v2 wouldn't work since it's SSL wouldn't work w/browser's SSL. They came out with beta version that fixed that, but now v3 reverted back. That's what I heard anyways...