If you plan on using your signature font in legal documents we strongly advise that you contact a lawyer and verify the legality of using digital signatures in documents. We suggest you read the following articles which relate to the use of digital signatures.

States with Digital Signature Legislation
A list of States with Digital Signature Legislation
Read More...

The verdict on plaintext signatures : They're legal
Summary: Contrary to conventional wisdom, commercial law generally does not require that a signature be "secure" to be legally effective. That is good news for e-mail, and electronic commerce in general.
Read More...

Legal issues - Digital Signatures (Canada)
The digital signature is one technological solution to some business, audit and legal problems with electronic commerce. While the digital signature solves some legal issues with electronic commerce, it raises its own legal issues.
Read More...

Legal issues - Digital Signatures (European Union)
Various links to digital signature issues in the European Union.
Read More...