A Curious Case Of A Dropped PR5 Domain

So I have found a nice 10 year old domain in my niche that was dropped. Link profile was nothing extraordinary, about 100 linking domains, couple PR1s and PR2s, but in archive.org I saw it had lots of real high quality content so I registered it.

About a week after it was indexed I saw the homepage pagerank jump to 5. I was like wtf? Checked link profile again but couldn't find the source of the juice. So I thought maybe somebody was trying to auction it before it expired and faked the pagerank. The next PR update should sort it out. Now this is the weird part. Yesterday there was a PR update. The PR5 homepage remained PR5, but all the inner pages are PR N/A just like before the update.

My confusion:

If there is an active redirect pointing to the domain, the inner pages should have picked up pagerank. Same if it's genuine PageRank.
If there was a redirect that has already been removed, then the homepage Pagerank should have dropped.

I am not fixated on pagerank, this is just something that doesn't make sense to me logically. Any ideas?

What's the domain url? Maybe wait a few more days and see what happens cause I know that google PR does some weird things... e.g. I had one of my sites jumped to PR7 all of a sudden and after a few days it went back down to PR4

What was the PR at the time you bought it?

could be a redirect.. is your interlinking structure right ?
what was the inner pages PR before the update ?

freezeice04 said:

What's the domain url? Maybe wait a few more days and see what happens cause I know that google PR does some weird things... e.g. I had one of my sites jumped to PR7 all of a sudden and after a few days it went back down to PR4

Click to expand...

Sorry, not outing the URL. It's been PR5 for about 2 weeks and this recent update made no difference.

qrazy said:

What was the PR at the time you bought it?

Click to expand...

It was N/A, was dropped for a couple weeks before I registered it again.

rambolife said:

could be a redirect.. is your interlinking structure right ?
what was the inner pages PR before the update ?

Click to expand...

The inner pages were n/a just like now. There are 12 inner links on the homepage, d0f0llow, robots.txt is set up correctly.

Without writing a white paper here on how PR works, sounds like you have nothing to worry about. It is a legitimate PR5. An expired-and-just-renewed/parked/crappy-content domain often shows PR N/A or PR0 and pops back to what it should be once it receives content again. No tool shows all your backlinks, but you do have a high PR backlink somewhere.