One example that works:
----
Some [[first]][[second]][[third]] text
----
And produces (tested chrome => 1.5.4.100) this output:
====
<div class="paragraph">
<p>Some <a id="first"></a><a id="second"></a><a id="third"></a> text</p>
</div>
====
The same is not possible with the anchor form:
----
Some anchor:first[] anchor:second[] anchor:third[] text
----
Produces:
====
<div class="paragraph">
<p>Some <a id="first"></a> <a id="third"></a> text</p>
</div>
====
As you see, each second anchor definition is lost.
The workaround:
----
Some anchor:first[] anchor:lost1[] anchor:second[] anchor:lost1[] anchor:third[] text
----
In my opinion this is a bug.