reshape2 1.4.4

• Fix R CMD check failure in R-devel.

reshape2 1.4.3

• Fix C/C++ problems causing R CMD CHECK errors.

• melt.data.frame() throws when encountering objects of type POSIXlt,
  and requests a conversion to the (much saner) POSIXct type.

reshape2 1.4.2

• Minor R CMD check fixes for CRAN.

reshape2 1.4.1

• melt.data.frame() now properly sets the OBJECT bit on value variable
  generated if attributes are copied (for example, when multiple POSIXct
  columns are concatenated to generate the value variable) (#50)
• melt.data.frame() can melt data.frames containing list elements as id
  columns. (#49)
• melt.data.frame() no longer errors when measure.vars is NULL or empty.
  (#46)

reshape2 1.4

• dcast() and acast() gain a useful error message if you use value_var
  intead of value.var (#16), and if value.var doesn't exist (#9). They
  also work better with . in specifications like . ~ . or
  x + y ~ .
• melt.array() creates factor variables with levels in the same order
  as the original rownames (#19)
• melt.data.frame() gains an internal Rcpp / C++ implementation, and
  is now many orders of magnitudes faster. It also preserves identical
  attributes for measure variables, and now throws a warning if they are
  dropped. (Thanks to Kevin Ushey)
• melt.data.frame() gains a factorsAsStrings argument that controls whether
  factors are converted to character when melted as measure variables. This
  is TRUE by default for backward compatibility.
• melt.array() gains a as.is argument which can be used to prevent
  dimnames being converted with type.convert()
• recast() now returns a data frame instead of a list (#45).