Crippled google search on partner sites?

Does google give different search results from partner websites

[ConorONolan]

A client called me today and asked why his site wasn't appearing in Google. I had created his humble site a few months earlier. So I opened google.ie and searched for the company name with the 'pages from Ireland' option selected. Lo and behold, there he was, first up. That was news to him. So I searched with 'the web' as the option and there he was again, first on the list.

However, turns out he was using the google search from his ISP (Eircom.net). So I tried there, and sure, his site wasn't in the search results even though I used the same search words.

So, does google deliberately or otherwise give different (older maybe) search results when the search comes from partner website and partner website is allowing unrestricted search?

Note1: Same result on AOL.com
Note2: Google search not effected by cookie because client saw same results

[edited by: tedster at 5:37 pm (utc) on Dec. 11, 2007]
[edit reason] no urls please [/edit]

[tedster]

From what I've seen recently, AOL and other Google Search partner sites do not currently get the Supplemental Index urls. That might account for what you're seeing. The total number of results for a search is probably lower, correct?

[ConorONolan]

You are correct about the lower number of search results on the partner website. Because my clients website is new and has almost nobody linking to it (he doesn't need it much) it could be supplemental.

However, if my clients site shows up as number 1 for main google search, clearly the search term is unique enough and appropriate. So why is it in google's interest for AOL and others to have a less relevant search?