Is changing your internet IP address illegal?

[biggeo65]

It iw your right to mask \ hide your IP address,nothibg illegal on that.

But tumblr has a term on their services as follow:
"(e) use the Services to send altered, deceptive, or false source-identifying information, including without limitation by forging TCP-IP packet headers or e-mail headers"

For me it's totally unfair term at least, but it's there, and when you sign up for tumblr,
you accept these terms, so they have any right to terminate your account.

You did nothing wrong, or actually the only wrong you did,was to sign up
with a company that has less concern about privacy.