After Canadian Solar (NASDAQ:CSIQ) reported some strong quarterly numbers last week, investors may have been eagerly anticipating results from countrymen JA Solar (NASDAQ:JASO) and ReneSola (NYSE:SOL). If so, they were sorely disappointed.

As I've been saying since Trina Solar (NYSE:TSL) saw light at the end of the tunnel back in March, integrated module makers currently occupy the best position in the solar supply chain. Canadian Solar's results were further evidence of that. The story is different with cell maker JA Solar and wafer purveyor ReneSola.

While JA Solar reported 159% higher revenue sequentially, gross margins were still anemic at 11.4%. In comparison, Canadian Solar's gross margins topped 20% this quarter. Various accounting charges led JA Solar to report an operating loss, which becomes a modest operating profit if you wave them all away. It's unclear why you would ignore an accounts receivable provision, which implies that some customer payments appear uncollectible. As for stock option expenses, those can be taken care of pretty easily -- just stop issuing them.

Last quarter, the missing element I identified at JA Solar was the lack of major supply relationships beyond the one with BP's (NYSE:BP) solar division. That situation is unchanged, and the cell slinger remains unappealing to me as long as this weakness persists.

As for ReneSola, long gone are the days in which the company was in wafer wonderland. This segment of the solar supply chain is no longer so dreamy. Both ReneSola and LDK Solar (NYSE:LDK) have a serious slump on their hands.

For the quarter, ReneSola saw revenue drop 23% sequentially, with gross margins barely registering at just 5%. Like JA Solar, the company reported a small operating loss.

Perhaps the only bright spot was the small, newly acquired module business, which reported gross margins in excess of 30%. Suddenly ReneSola isn't looking so crazy for moving onto its customers' turf through this radical reshaping.

Fool contributor Toby Shute doesn't have a position in any company mentioned. Check out his CAPS profile or follow his articles using Twitter or RSS. The Motley Fool has a disclosure policy.