Bing Crosby’s “White Christmas”

I recently got the European version of Bing Crosby’s White Christmas CD from a local store here in Sweden, cat. no. MCD 18226. I discovered that this version is different from the US one; the European version seems to be based on a 1963 LP release of Merry Christmas, which is in “simulated stereo” and which has added reverb, while the US version is based on the 1955 release, which is in mono with no reverb.