Where is the Buddha originally quoted as saying "On heaven and earth, I alone am honored"? In Chinese and especially Japanese Buddhism, the statement 天上天下唯我独尊 (Japanese tenjou tenge yui ga dokuson; not sure about the Chinese transliteration), which is typically translated as "On heaven and earth, I alone am honored", is considered to be a well-known statement of the Buddha, spoken when the Buddha first emerged from his mother's womb. The quote is sometimes truncated to just the latter half 唯我独尊 "I alone am honored". 

I have done a fair bit of searching for a Sanskrit/Prakrit source from which this quote could have been translated into Chinese, but have had no success so far. What text serves as the origin of this quotation? Did it only first appear after the spread of Buddhism into China?
The Pali version isn't quite as strong. According to Malalasekera:

Immediately after birth the Bodhisatta stands firmly on his feet, and having taken seven strides to the north, while a white canopy, is held over his head, looks round and utters in fearless voice the lion's roar: &quot;Aggo 'ham asmi lokassa, jettho 'ham asmi lokassa, settho 'ham asmi lokassa, ayam antimā jāti, natthi dāni punabbhavo” (D.ii.15).
http://www.palikanon.com/english/pali_names/b/buddha.htm

The meaning of the phrase is &quot;I am the highest in this world; I am foremost in this world; I am the best in this world; this is the last birth; there is no further becoming here.&quot;
Nothing I've found specifying heaven and earth; it also doesn't seem proper for the Bodhisatta to have said &quot;I alone am honoured&quot;, since it is patently untrue.