Equivalent Metrics: Convergent Sequences?

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Is it true that two metrics d_1 and d_2 on a set X are equivalent iff they have the same convergent sequences (i.e., a sequence that converges in d_1 converges in d_2 and vice versa)?
 
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Yes.

Engelking, "General Topology", Thm. 4.1.2

"Two metrics on X are equivalent iff they induce the same convergence."
 
Yup, although the correct term is "topologically equivalent", since metrics can also be "uniformly equivalent" or "Lipschitz equivalent" and there might be more such equivalencies.