FOSS gamedev and creative worlds

So I created 50 ladders, placed 3, and the remaining 47 were placed as 1 [ONE]. After mining it, there was 1 [ONE] ladder in my inv.

[winXP, minetest 047]

Is this reproduceable somehow?
Also, have you played singleplayer or on a server? If one a server, which one?

Singleplayer. Idk if it's reproducable, but it happened twice for me. both times i was in a 1*1 hole and I was ON the ladder, putting ladders upwards. I can't tell anything more till monday, cause i can play only @ work, cause on my home PC the game won't run (GF 5200, Athlon 1800, 512 ram)