iteration section #object[property]:key disappears

[luxferre]

v0.6.1
data:

{
    selectedKey: 'key1',
    heap: {
        key1: {
            a: 'optiona',
            b: 'optionb'
        },
        key2: {
            a: 'optiona',
            b: 'optionb'
        },
        key3: {
            c: 'optionc'
        }
    }
}

template:

<p>keys</p>
<ul class="select">
    {{#heap:key}}
    <li on-click="selectKey">{{key}} click me</li>
    {{/heap}}
</ul>
<p>available options for {{selectedKey}}</p>
<ul>
    {{#heap[selectedKey]:option}}
    <li>{{option}}</li>
    {{/heap [selectedKey]}}
</ul>

when I click key2 and then key1, section '#heap[selectedKey]:option' disappears
or when I call "ractive.set('selectedKey', 'key2');ractive.set('selectedKey', 'key1');" in console

jsfiddle: http://jsfiddle.net/luxferre/6ocsamw7/5/
I've tried "#each" syntax with no success http://jsfiddle.net/luxferre/6ocsamw7/6/