Acrobat only presents signature panel to sign form

Does anyone have experience with Acrobat Reader not presenting the typical signature options, but only presenting a blank signature drawing window?  On some computers it is presenting the typical options for adding a signature as expected, but on other machines the very same form presents only the signature draw window when the signature field is clicked.  This is happening even when the computer doesn't have a signature pad device attached to it.  Any idea of what to check to present the regular signature options?
Thanks!